■ Britain observed a nationwide moment of silence at 11 a.m. Thursday to mourn the victims.
■ The New York Times was given access to photographs of materials found at the scene of the Manchester bombing that show a detonator, shrapnel and a battery.
■ The American pop singer Ariana Grande is suspending her tour until at least June 5. It was after her concert in Manchester that the terrorist attack occurred.
View more photographs from the investigation and aftermath of the attack here.
Abedi’s Brother and Father Arrested in Libya
A powerful Islamist militia in Tripoli said on Wednesday that it had arrested Mr. Abedi’s 20-year-old brother, Hashem, at the family’s home in the Libyan capital on Tuesday, and said that he was a member of the Islamic State who was planning an attack in Tripoli.
“We have been following him for at least a month and a half now,” said Ahmed Omran, a spokesman for the militia, known as the Special Deterrence Force.
Later, Mr. Omran said the group was also holding the father, Ramadan Abedi, who is also known as Abu Ismail.
The Special Deterrence Force, or Rada, is one of the most powerful militant groups in the often lawless capital. Its leaders are staunch Islamists and it operates a detention facility where many people suspected of being Islamic State fighters have been held.
Mr. Omran said that Hashem Abedi had told the militia that he was “kept in the loop about the attack” in Manchester by his brother, and that the group had said in a Facebook post that Hashem was involved in the planning of the bombing, although it offered no proof.
The militia also said that Hashem traveled to Libya from Britain on April 16, and that he had been in daily phone contact with his older brother since then.
8 in Custody After Latest Arrests
The Greater Manchester Police said on Wednesday night that two more people, a man and a woman, had been arrested in connection with the investigation. The man was taken into custody in Nuneaton, Warwickshire, in central England, according to the police. The woman was arrested during raids in the Blackley area of Manchester, north of the city center. The police provided no further details.
Early on Thursday morning, the police announced that they had arrested another man in the Withingon area, in the south of Manchester, adding that the woman arrested in Blackley had been released without charge.
Eight men are now in custody in connection with the attack, the police said on Thursday.
‘I Don’t Believe That It Was Him’
Before his arrest by the Special Deterrence Force in Libya, the bomber’s father said in a phone interview that his son Salman could not have carried out the attack on the Manchester Arena.
“I don’t believe that it was him,” said the father, Ramadan Abedi. “His ideas and his ideology were not like that. He was born and raised in Britain. He’s a British citizen and he does not hold such ideologies.”
Salman Abedi, born in Manchester in 1994, had recently visited his parents, who had moved back to Libya after living for decades in Britain. The father, speaking from Tripoli, said he believed that his son was on his way to make a religious pilgrimage at the time of the attack.
4 More Victims Identified
Four more victims of the Manchester Arena attack have been identified.
Eilidh MacLeod, 14, of the Isle of Barra, in Scotland. “Our family is devastated and words cannot express how we feel at losing our darling Eilidh,” the family said in a statement. “Eilidh was vivacious and full of fun. She loved all music whether it was listening to Ariana or playing the bagpipes with her pipe band.”
Chloe Rutherford, 17, and Liam Curry, 19, of South Shields, in northeast England: “On the night our daughter Chloe died and our son Liam died, their wings were ready but our hearts were not,” the families said in a statement posted on Facebook. “They were perfect in every way for each other.”
Elaine McIver, a Cheshire police officer: “Elaine just loved life, and had a major love of music. Despite what has happened to her, she would want us all to carry on regardless and not be frightened by fear tactics, instead she regularly urged us all to rise up against it.”
Manchester Bomber Was Part of a ‘Network’
Investigators have been focused on determining who may have helped the bomber, Mr. Abedi, plan and execute the attack at the Manchester Arena after an Ariana Grande concert.
“It seems likely — possible — that he wasn’t doing this on his own,” Britain’s home secretary, Amber Rudd, said on Wednesday.
Chief Constable Ian Hopkins of the Greater Manchester Police said at a news conference on Wednesday, “This is a network that we are investigating.”
He did not specify whom the police were looking for, or if investigators were searching for a bomb maker.
“There’s an extensive investigation going on, and activity taking place across Greater Manchester as we speak,” he said.
Four men were arrested on Wednesday — three in Manchester and one in Wigan, a town to the northwest — as the number of people in custody, including Mr. Abedi’s older brother, continued to rise. What role, if any, they played in the attack is unclear.
Evidence photographed and collected at the crime scene suggests an improvised device made with forethought and care.
The BBC, citing unidentified intelligence sources, reported on Wednesday that officials believed Mr. Abedi had been a “mule,” carrying a bomb made by someone else.
Officials are still trying to find the “factory” where the bomb was made and to discern whether Mr. Abedi received help assembling the device, according to a law enforcement official who spoke on the condition of anonymity because of the secrecy surrounding the investigation.
Officials are also looking into reports that people who knew Mr. Abedi — including an imam at his mosque — contacted the authorities as much as two years ago with concerns that he had become radicalized.
Salman Abedi’s Possible Radicalization
Friends and neighbors of Salman Abedi have said he expressed extremist views, and a security official has said he traveled to Syria, the stronghold of the Islamic State.
In 2015, according to a neighbor of the Abedi family who spoke on the condition of anonymity because of safety concerns, the imam at the mosque the family attended delivered a sermon condemning terrorism and murder carried out in the name of a political cause. The sermon by the imam, Mohammed Saeed, prompted a heated discussion among congregants, some of whom signed a petition taking issue with it, according to the neighbor.
“He was angry,” the neighbor said of Mr. Abedi. “He scared some people.”
A friend of Mr. Abedi, who also spoke on the condition of anonymity because he feared for his safety, said that the assailant, along with other young men of Libyan descent in Manchester, had been deeply angered by the gang killing last year of a friend, Abdul Wahab Hafidah.
It was around this time, according to people who knew the family, that Mr. Abedi traveled to Libya to see his parents. He also traveled to Syria, according to the French interior minister, Gérard Collomb.
Mr. Collomb said that Mr. Abedi had “proven” ties to the Islamic State, but he did not give details. It was not clear whether Mr. Abedi’s visits to Libya and Syria were part of the same trip.
During Mr. Abedi’s visit to Libya, his parents became worried about his radicalization, and even seized his British passport, according to the friend in Manchester.
Mr. Abedi’s father denied this. He said in a telephone interview on Wednesday that his son was not an extremist and was in possession of the passport because he was traveling back to Manchester before going to Saudi Arabia for a religious pilgrimage.
Muslims in Manchester Urged to Help Police
Officials from the mosque the Abedi family attended said on Wednesday that anyone with information about Mr. Abedi should cooperate with the police investigation.
Speaking outside the Manchester Islamic Center, also known as the Didsbury Mosque, one of the mosque’s trustees, Fawzi Haffar, said, “We encourage anyone, and I repeat, we encourage anyone who may have information about the individual involved to contact the police without delay.”
Security Bolstered Around the Country
The military, under the code name Operation Temperer, has been deployed to vital locations around Britain to assist police officers in protecting against another terrorist attack.
“This frees up armed police officers to then give the police service the capacity to then deploy them to places like Manchester,” Chief Constable Hopkins said, adding, “There are no military personnel patrolling the streets of Greater Manchester, nor are there plans for that to happen at this time.”
Intelligence Leaks Upset British Security Officials
The British police identified Salman Abedi on Tuesday after several news organizations in the United States, including CBS News and USA Today, citing American intelligence sources, had already done so.
Ms. Rudd, Britain’s home secretary, made clear on Wednesday the government’s dismay at the leaks.
“British police have been very clear that they want to control the flow of information in order to protect operational integrity, the element of surprise,” she told BBC Radio 4. “So it is irritating if it gets released from other sources, and I have been very clear with our friends that that should not happen again.”
Asked whether the American leaks had compromised the investigation, she replied, “I wouldn’t go that far, but I can say that they are perfectly clear about the situation, and that it shouldn’t happen again.”
Victims’ Families Have Been Notified
All of the families of the victims of the Manchester bombing have been notified by the authorities, Chief Constable Hopkins said on Wednesday.
One of the 22 people killed was a police officer on duty at the time of the bombing, but out of respect for the officer’s family, the police will not identify him.
It will take another four or five days to publicly identify all of those killed, Chief Constable Hopkins said.
At a vigil in Albert Square on Tuesday evening, Mancunians gathered to honor those who were killed in the bombing the day before.
Olivia Roberts, 15, who attended the concert but escaped injury, was still wearing her Ariana Grande tour T-shirt with blood stains on it. She hugged her mother, Lorraine, who was with her at the vigil.
“I brought her here because she needs to process what has happened,” Lorraine Roberts said of her daughter. “She needs to grieve.”
She stroked her daughter’s head with one hand and held up a bouquet of flowers with the other. “This is the world we live in now,” she said. “We have to face up to it.”
Azam Mirza, 24, attended the vigil with a homemade placard that read: “Hate no one, Love everyone.”
“Journalists asked me if I was nervous to come out here today — why?,” Mr. Mirza, who is Muslim, said. “I’m here to support my community and condemn these hateful acts, just like everybody else.”