British counterterror police say the investigation into Monday's deadly bombing after a concert in Manchester is "making good progress", but that authorities can not say yet whether the man responsible for the attack was part of a wider group.
Rudd confirmed in an interview with the BBC that Abedi was on the radar of intelligence services and that he had recently returned to the United Kingdom from Libya.
Armed police is on patrol in central Manchester, Britain, Wednesday.
Officials are probing how often Abedi had traveled to Libya, which has seen an eruption of armed Islamist groups since dictator Moammar Gadhafi was overthrown and killed in 2011.
Ms Rudd confirmed Abedi had recently returned from a visit to Libya, where his parents are reported to now live, and said the nature of the attack suggested he may have had support.
Britain ordered soldiers to key sites Wednesday and raised the terror alert to maximum after the Manchester concert suicide bombing by a local man of Libyan origin who may have been radicalized in Syria.
Abedi was named after armed officers carried out a raid and controlled explosion at an address in south Manchester where he was registered as living.
What we know about Salman Abedi, the Manchester bombing suspect
Asked about reports that Abedi had recently returned from Libya , Rudd said she believed that had now been confirmed. Police raided a property in the Manchester district of Fallowfield where they carried out a controlled explosion.
She also complained about US officials leaking sensitive information about Abedi to the press.
She said the deployment of troops would enable the police to step up security at various high profile events over the coming days, including the Great Manchester Run.
"It is somebody that they had known and I'm sure when this investigation concludes we'll be able to find out more", she said. This means another attack is imminent in the United Kingdom and military personnel will be deployed in key locations to help armed police protect the public.
At least 12 victims aged 16 or under were being treated at a children's hospital for serious injuries, some of them fighting for their lives, a Manchester health official 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. 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".
Collomb, who spoke with British Prime Minister Theresa May after the attack, said the two countries should continue cooperating closely on counterterrorism efforts despite Britain's pending exit from the European Union.
Mark Rowley, who heads the National Counter Terrorism Policing, said late Tuesday that searches were ongoing and officers were following "a number of investigative leads".