The Washington PostDemocracy Dies in Darkness

Signs of the Manchester attacker’s possible radicalization appeared more than a year ago

Salman Abedi's acquaintances were stunned to learn that he was the man believed to have carried out a suicide bombing at a concert hall this week, killing 22 people. But there were signs that he was troubled — and he was not the only one in his family who caused concern, friends and officials said Wednesday.

Salman’s 20-year-old brother Hashem was arrested in Libya late Tuesday night, according to officials there, who said the young man told authorities that he had been involved in planning the attack on the concert hall in Manchester. British and other European security officials said they did not believe that Salman Abedi, 22, would have been able to build the explosive device used in Manchester by himself, and they worry that a professional bombmaker may still be at large.

Armed troops guard Buckingham Palace and other London landmarks after Manchester attack

In the Libyan-British community in southern Manchester where Salman Abedi lived, he was known as a university dropout and loner, acquaintances said. Abedi was born in Britain to parents who had fled Libya during the four-decade dictatorship of Moammar Gaddafi, and moved back to their homeland several years ago, after the Libyan leader was killed.

Residents described Abedi as an “awkward” young man and an “isolated, dark figure” who talked to few people and traveled back and forth between Britain and Libya.

Here's what you need to know about Salman Abedi, the 22-year-old attacker who killed 22 at a concert in Manchester, England. (Video: Sarah Parnass/The Washington Post)

Abedi’s father, Ramadan, asked two of his sons to move from Britain to Libya several weeks ago, said a friend of the family who last spoke to the father on Tuesday.

“The father said he was afraid that something would go wrong if they stayed in Britain,” said the friend, who spoke on the condition of anonymity for security reasons. The friend did not describe the nature of the father’s concerns.

But the friend said Salman and his brother Hashem had changed after another youth — an 18-year-old Manchester resident also of Libyan descent — was killed in the northern ­British city a year ago. That teenager, Abdulwahab Hafidah, was stabbed in the neck in what local media reports called retaliation for his having gone into rival gang territory.

“It became a big source of anger for the youngsters in the Libyan community. Salman and Hashem saw it as an act of anti-Muslim hate crime; they called him a martyr,” the family friend said. Hashem Abedi appeared to have known Hafidah.

Members of the Libyan immigrant community reported to local authorities more than a year ago that they feared Salman Abedi was turning increasingly radical, two friends of the family said. British security authorities have acknowledged that they were aware of Abedi but said that he was not considered a major terrorism risk.

Ramadan Abedi told the Associated Press early Wednesday that he believed his son was innocent. "Last time I spoke to him, he sounded normal," the father said in a telephone interview from Libya.

Still, Abedi and his wife took away their son’s passport upon his arrival recently in Libya, where both brothers were supposed to celebrate the Muslim holy month of Ramadan, Libyan authorities said, citing testimony by Hashem Abedi.

The young men’s mother returned the travel document about one week ago when Salman told his parents he wanted to travel to Saudi Arabia to prepare a pilgrimage to Mecca, according to one family friend and a Libyan official.

“But he was lying,” said Ahmed Dagdoug, a spokesman for the Libyan counterterrorism Reda Force, which is aligned with the Libyan government that is recognized by the United Nations.

Instead of going to Saudi Arabia, Abedi flew back to Britain, where he is suspected of carrying out the worst terrorist attack on British soil since the London bombings in 2005.

The Manchester attack was exactly what many had long feared

Authorities worry that Abedi might be part of a network of terrorists, many of whom may remain at large. “Abedi appears not intelligent enough to have built this bomb himself. That’s why there are concerns that a bombmaker is still out there,” said a European security official, speaking on the condition of anonymity to discuss intelligence matters.

Investigators are also still trying to determine whether Abedi received support from family members. Libyan authorities arrested Hashem Abedi, alleging that he was aware in advance of the Manchester bombing plot and was also planning an attack in Tripoli. His father, who had been working for the Libyan police force in recent years, according to an official, was also detained on Wednesday, although it was not clear on what grounds.

“Hashem helped Salman prepare for the attack,” Dagdoug said. “He had the same ideology as his brother.”

Dagdoug said he didn’t know precisely how Hashem assisted his brother. But Hashem told interrogators that “we knew what we were doing,” Libyan officials said.

Salman Abedi appeared to leave few traces of his life on social media, but there are indications that his younger brother may have been attracted to extremism. In 2014, Hashem joked on Facebook about joining a militant group, commenting on the photo of a young British jihadist who had left for the war in Syria: “Inshallah [God willing] we go together.” The younger brother’s Facebook profile revealed other signs that he had an interest in the Islamic State, which has asserted responsibility for the Manchester attack.

In suburban Manchester, a search for what might have motivated the attacker

Although British authorities asked members of Salman Abedi’s southern Manchester community not to speak to the media, people who knew the family said on Wednesday that Abedi cared for his parents. “He really liked them,” said Mohammad Fadi, 25, standing in front of the mosque where the family had worshiped.

Salman Abedi was born in Manchester in 1994. His father sometimes led the call to prayer at the local mosque, the Manchester Islamic Center, and his older brother, Ismail, sometimes volunteered there. Ismail has also been taken into custody since the attack.

When the parents moved back to Libya a few years ago, their sons stayed behind in Manchester.

Salman Abedi studied briefly at Salford University, in Manchester, but wound up dropping out.

“Salman was rarely seen there by other students,” said community member Fadi.

At the mosque that the Abedi family attended, no one spoke in favor of the attack.

“This act of cowardice has no place in our religion,” said Fawzi Haffar, a trustee at the center.

Raghavan reported from Tripoli. Isaac Stanley-Becker in Manchester contributed to this report.

Today’s coverage from Post correspondents around the world

Like Washington Post World on Facebook and stay updated on foreign news