But the steady stream of information appearing in US press has persuaded Greater Manchester Police to take the extraordinary step of no longer sharing information on the investigation with the Americans, the BBC reported.
British police lifted the ban in less than 24 hours, but only after Prime Minister Theresa May personally confronted President Trump in Brussels, where both leaders are attending the North Atlantic Treaty Organisation summit.
Meanwhile, British Transport Police says armed officers will patrol some United Kingdom trains for the first time because of the increased threat of extremist attacks.
"The public should remain vigilant", she said, following an emergency ministerial meeting. Police are rushing to uncover the network thought to have helped Abedi in the attack.
British media reported that Abdul Wahab Hafidah died after being run over and stabbed in the neck in Manchester's Moss Side district in May previous year. Meanwhile, officials probed possible travel by the alleged bomber, looking for clues to new threats.
"These relationships enable us to collaborate and share privileged and sensitive information that allows us to defeat terrorism and protect the public at home and overseas", the spokesman said. Abedi's brother and father were arrested by a militia in that country after the bombing, the militia said.
The name of the man arrested in the early hours Friday and those of the eight others in custody were not released.
She said that the victims were very young people, which points to the fact that the Manchester bombing was a clear attack on the European youth and their love of life.
Residents gathered in a large circle in the city's St. Ann's Square with heads bowed before a makeshift memorial of flowers, balloons and candles dedicated to the 22 people killed when Salman Abedi detonated an improvised device just moments after a concert by American pop singer Ariana Grande.