Manchester Police and United Kingdom officials are still they were working to determine whether Manchester suicide bomber Salman Abedi was operating as a lone wolf, of working with a larger terrorist network.
Soldiers were being deployed to key sites in Britain on Wednesday to prevent attacks after the terror threat level was raised to its highest level following a suicide bombing in Manchester that killed 22 people, including children.
Bomb makers on the loose have wreaked havoc in past European terror attacks.
The Islamic State were quick to claim responsibility for the attack early Tuesday, but it is not yet known whether Abedi was working with anyone else.
The police chief announced that authorities had arrested three more men suspected of being involved in the arena bombing after Ariana Grande's concert. It brings to four the total number of people who are being questioned by police after a 23-year-old male was detained yesterday.
Within minutes, police in Britain's third city of Manchester knew they had a major incident on their hands after a bomber targeted the youngsters leaving the performance in one of Europe's largest indoor venues.
Other victims to have been named so far include Martyn Hett, 29, and 18-year-old Georgina Callander. "This will free up armed officers to carry out patrols", the police said.
In a statement, the head teacher of the Tarleton Community Primary School that she attended in the village of Tarleton, Lancashire, described her as "simply a handsome little girl in every aspect of the word".
They are both now in separate hospitals being treated for injuries, friends said. Numerous wounded are said to have metal fragments and bolts embedded in their body.
22-year old Abedi was born in Britain to Libyan parents.
Justin Trudeau photobombs kids en route to prom
The same month, a Canadian family stumbled on him emerging from a cave while hiking in Quebec's Gatineau Park. Trudeau tried to get out of the way, but ended up being a part of the photos inadvertently.
The suspected bomber grew up in Manchester's southern suburbs and once attended Salford University there.
Abedi and another brother stayed behind to finish up school, the news service reported.
Speaking on BBC News on Wednesday morning, Home Secretary Amber Rudd said the measure would be temporary, but would not be drawn on whether this meant days or weeks.
The summit is to be joined by US President Donald Trump, who has lambasted North Atlantic Treaty Organisation for not doing more against Islamist extremism and who called those responsible for the Manchester bombing "evil losers".
"The British police have been very clear that they want to control the flow of information in order to protect operational integrity, the element of surprise, so it is irritating if it gets released from other sources, and I have been very clear with our friends that should not happen again."
"As yet the tour is not officially postponed or cancelled, despite media reports".
"The reality is that we must be prepared to be able to respond to and deal with armed and deadly attackers, so we must be in a position to respond with firearms officers who will use force to stop those attackers in their aim", she said in a statement.
Speaking at a press event, senior ranking Democrat on the House intelligence committee Adam Schiff said that if USA officials did leak details of the investigation then that would mean the U.K would "have every right to be furious with us".
"This is nonsense", he commented, adding that under Gadhafi, "anyone who went to a mosque raised question marks".