British police have arrested two more men in connection with the Manchester attack, taking the number of people in custody to eight, Greater Manchester police said.
In the early hours of Thursday morning, counter-terror police carried out a controlled explosion at a property in the Moss Side area of Manchester, although no arrests were reported by police.
A third suspect, a local woman, was also arrested Wednesday overnight during an armed raid but was later released without charges.
Police hunting the terror network behind the Manchester Arena bombing have stopped passing information to the USA on the investigation as a major transatlantic row erupted over leaks of key evidence in the U.S., according to a report.
Prime Minister Theresa May is expected to raise United Kingdom concerns when she meets US President Donald Trump at a North Atlantic Treaty Organisation meeting in Brussels on Thursday.
Salman Abedi's brother and father were arrested in Libya Wednesday..
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Ramadan Abedi had earlier claimed his son Salman was innocent, saying: "We don't believe in killing innocents".
Abedi, a 22-year-old British citizen born to Libyan parents, died in the attack, which targeted fans leaving a concert by U.S. pop star Ariana Grande.
Counterterrorism officials fear that whoever built the bomb, used in the attack that killed 22 people and left 59 wounded outside an Ariana Grande concert, may have made other devices that could be used in future attacks.
Sources said the family are from Cheshire.
"It's really suggesting that he probably did not act alone, that he probably had some help, that he certainly had some advice on how to create the bomb", Olsen said.
Ian Hopkins, chief constable of the Greater Manchester Police, said it's "very clear" they are investigating a possible network behind the blast. "So after that, he told us, "Having internet, I see the attack in Manchester and I knew that's my brother".