A representative of the Quilliam Foundation has said Islamic State most likely became aware of the terror attack in London "at the same time as we did."
Eight people have now been arrested in connection of the attack on Westminster, where four people - including the attacker - died and up to 40 were injured.
Isis have claimed responsibility via a press release from their news agency. But Jonathan Russell, head of policy at the anti-extremism foundation, said the wording of these release suggests the terror group is merely seeking to exploit the fervour caused by the tragedy.
He told Julia Hartley-Brewer: "We know from the Met Police statement yesterday it was linked to islamist terrorism already.
“However, Isis traditionally take credit for a lot of things they may not have directed or direct control over. This press release I’m looking at at the moment, they frame this attack as “inspired” not “directed.”
"This distinction is important because means they probably didn’t know of it until we did and didn’t command it.
“This means they know their strength is through inspiring and motivating attacks via their ideology without having to take the risk of coordinating things."