Paris: David Cameron warns 'we must be prepared for British casualties' in attacks

The Foreign Office is 'urgently investigating' whether any British nations were caught up in the attack

David Cameron called a COBRA crisis response committee meeting following the Paris attacks (PA)

David Cameron has warned that "we must be prepared for a number of British casualties" after the "brutal" attacks in Paris.

More than 128 are feared dead following coordinated gun and bomb attacks throughout the French capital.

The Foreign Office has said it is "urgently investigating" whether any British nations were caught up in the shootings or hostage-taking.

Following a COBRA meeting this morning, Mr Cameron made a statement calling the attacks the "worst act of violence in France since the Second World War".

"These were innocent victims enjoying a Friday night out with family and friends... simply going about their way of life, our way of life."

Mr Cameron said Isis "want to destroy everything our countries stand for - peace, tolerance, liberty - but we will not let them."

He went on to say Britain will "redouble our efforts to wipe out this poisonous, extremist ideology".

Police and intelligence services are "working around the clock" and constantly learning lessons about Isis' "evolving" threat, he added.

British police have said there will be strengthened policing at ports and increased policing at public events in the coming days.

Meanwhile, French President Francois Hollande addressed the nation, and vowed a "merciless" response to the attacks, which he said were perpetrated by Isis.