The New York Times posted leaked images of the remnants the suicide bomber's device on Thursday.
Authorities investigating the Manchester Arena explosion are likely to probe the bomber's links to Libya, where he spent three weeks before returning to the U.K. to carry out the attack.
The pair put on a strong display of unity following the bombing, which left 22 people dead and at least 50 others injured.
"The worst of humanity was on display in Manchester last night."
On Manchester's Curry Mile and in its mosques, people are wondering how terror came to their city.
Ramadan Abedi denies his son's involvement in the attack on Manchester Arena.
Manchester police said they have made three additional arrests in connection to the bombing that killed 22 people.
EU security commissioner Julian King said in March that about 850 Britons had traveled to fight in Syria.
The 37-year-old was due to board a flight for Turkey Tuesday evening.
Abedi blew himself up with an improvised explosive device, killing 22 after an Ariana Grande concert.
"it just doesn't feel real." Hundreds gathered for a vigil to remember the 22 victims of Monday's attack.
Top spies say European security services are more disciplined than their U.S. counterparts.
Justin Bieber shares a manager with Ariana Grande, who had just finished performing when a bomb detonated at Manchester Arena.
The attacks demonstrate the remarkable adaptability and scale of the ISIS threat that faces Western societies.
More than 22 people died after a violent attack at a concert in Manchester, U.K. on Monday.
Alex Jones on the Manchester Arena attack that left 22 people dead: "A big bomb goes off at a pop star's rock concert bombing a bunch of liberal trendies."
Viktor Ozerov, chairman of Russia's defense committee, says Britain is at fault for not working with Moscow.
The Queen condemns "act of barbarity" in the northern English city.
The suicide bombing killed 22 people, including children, on Monday night.
Security services cannot prevent attacks in every public area, says former MI6 chief.