Officials are examining Abedi's trips to Libya as they piece together his allegiances and try to foil any new potential threats.
The arrest was made following searches at an address in the town of Nuneaton in central England, and is the first outside the Manchester area.
After UK's terror attack on Monday night that left 22 people killed and at least 59 injured, Prime Minister Theresa May on late Tuesday said the threat level was now considered "critical", meaning an attack may be imminent. The changing of the guard ceremony at Buckingham Palace was canceled so police officers could be re-deployed.
Under Operation Temperer, up to 5,000 soldiers are being deployed to transport hubs and other crowded public places, in order to release the armed police for other duties.
Meanwhile, a Libyan security spokesman says the father of the Manchester bomber has been arrested in Tripoli.
At one apartment building in Manchester, heavily armed police swarmed in and a controlled explosion was heard.
Speaking of the woman, who was badly hurt from the bombing with serious leg and head injuries, he said: "She passed away in my arms".More news: Israeli joy at Trump visit, but substance lacking
Under normal circumstances, he said, Abedi may have been able to travel to the United States because he was from Britain, a visa-waiver country, but he would have been subjected to a background check via the USA government's Electronic System for Travel Authorization, or ESTA.
London, May 25 manchester Arena suicide bomber Salman Abedi had links to an Islamic State cell which operated in the city, and knew one of the terror group's most prolific recruiters, Sky News claimed today.
Minister Gerard Collomb said Wednesday on BFM television that British and French intelligence have information that Abedi had been to Syria.
"However, a critical line of inquiry is whether the dead terrorist was acting alone or part of a group", he said.
In the interview, Ramadan said that he last spoke to Salman two days before the Manchester attack, and that Salman was about to go on a pilgrimage in Saudi Arabia.
"I'm very clear that the police and the security services have the resources to ensure that they continue their investigation".More news: Boston Celtics vs. Cleveland Cavaliers - 5/25/17 NBA Pick, Odds, and Prediction
The Manchester bombing is the worst terror attack in the United Kingdom since the London bombings in 2005 that killed 56 people.
"The attacker himself could have been a young adult who may have got instruction to take out the infidels who are youth", he said.
Many of those still hospitalized had serious wounds that will require "very long term care and support in terms of their recovery", Rouse said.
Eilidh's friend, Laura MacIntyre, 15 - who was also reported as missing - was later identified as one of the seriously injured in a Manchester hospital.
Soldiers were sent to assist armed police at strategic sites in what is the first deployment of troops on British streets since 2007. London Police Commander Jane Connors said the goal is to "make our city as hostile an environment as possible for terrorists to plan and operate".
The National Counter Terrorism Policing body said the breach of trust caused great "damage" and "undermines our investigations". "And our values, our country, and our way of life will always prevail".More news: 3 more arrested in Manchester bombing
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