On Monday, it was reported that the Federal Bureau of Investigation had warned their United Kingdom counterparts that Manchester suicide bomber Salman Abedi was planning a deadly act of terrorism in the United Kingdom months before he carried out the attack on an Ariana Grande concert that left 22 dead.
Did you see Abedi with this suitcase between the 18 and 22 May 2017?
For the first time, suspected Islamist terrorists are being prevented from returning to the United Kingdom, the home secretary has said, as she warned that members of the Manchester bomber's terror network could still be at large.
The home secretary said ISIS was trying to "weaponise" young Britons and defended the work of the UK's security services following claims that warnings about Abedi were not followed up.
"There are hundreds of thousands of bits of intelligence that come into both MI5 and the police anti-terror hotline which have to be investigated".
"There remain a number of things that concern us about his behaviour prior to the attack and those of his associates which we need to get to the bottom of".
"I think it is the right first step", she said.
MI5 has launched two urgent inquiries into how it missed the danger posed by bomber Salman Abedi, the Guardian newspaper reported.
"It is right that MI5 take a look to find out what the facts are. We shouldn't rush to make any conclusions at this stage".
In a BBC television interview on Sunday, Rudd was quizzed over whether MI5 has the resources to keep on top of the terror threat. She said MI5 is now recruiting 1,900 new staff and its budget "has gone up significantly".
The 23-year-old was held on suspicion of terror offences at an address in Shoreham-by-Sea in the early hours of today, Greater Manchester Police (GMP) said.
The security service, otherwise known as MI5 has started an internal review over how they handled intelligence on Salman Abedi, who was the suicide bomber at last week's Manchester Arena. Sixteen arrests have been made in the investigation so far.