By William James
LONDON (Reuters) - Leaving the European Union would have serious consequences for Britain's security, the head of EU's law enforcement agency Europol said on Tuesday, warning that negotiating security pacts from outside the bloc would be a "damage limitation exercise".
National security has become a key area of contention between rival campaigners as Britain prepares to vote in a June 23 referendum on whether to stay in the EU, particularly in the light of Islamic State attacks in Paris and Brussels.
"I think there are some pretty serious security consequences actually," Rob Wainwright told Reuters. "If we accept that the EU does provide an important part of our security ... then the debate moves on to how do we mitigate that potential loss, so it becomes a damage limitation exercise."
Prime Minister David Cameron, who champions Britain's continued membership of the bloc, says the country would be safer inside the EU. Rival campaigners argue that greater control over immigration would reduce the threat, and that intelligence-sharing would not be harmed by an EU exit.
"If you put at risk any part of the framework for international police cooperation and intelligence sharing, that Britain currently relies on then there clearly is potential for consequences," Wainwright said in an interview on the sidelines of a security exhibition in London.
He said he would expect Britain to get associate membership of Europol, similar to that which the United States and Canada currently have, but that that arrangement would not give the UK direct access to its databases on suspected militants.
"Useful access, certainly, but just not as good," he said.
He said there would also be uncertainty about Britain's access to the Schengen Information System, which shares data on criminal suspects within the passport-free zone in Europe, and its use of the European Arrest Warrant, which allows easier extradition of criminal suspects inside the EU.
"I have no doubt that Britain will secure at least partial access to most of the systems, but that access will be variable and it will depend on many factors," he said.
BRUSSELS BOMBINGS
Speaking after suicide bombers in Brussels killed 32 people last month and November's attacks in Paris left 130 people dead, Wainwright said some of those responsible may not yet have been apprehended by police.
"I'm not entirely confident," he said when asked whether all the organisers had been detained. "That's because we have a fragmented intelligence picture of precisely who is involved and where they are."
He said he was "certainly not confident" that other attacks were not being planned, and that the number of people who could be involved in planning such attacks in Europe was "not necessarily in the thousands, but in the hundreds".
Wainwright said there had been a strategic shift in the approach of Islamic State (IS) towards pushing "battle hardened" militants back into Europe from Syria with the specific intention of carrying out spectacular attacks.
"It is not alarmist to say there could certainly be more cells out there planning these attacks - it is certainly the intention of IS," he said.
Speaking publicly later, he said that militants were being radicalised much more quickly - in weeks, not months and years - and that the profile of those militants was changing.
"Many of the individuals we have identified and are helping to track are motivated less by religious zealotry and more by an idea that they are ... military heroes carrying out a campaign - perhaps in keeping (with the) PlayStation games that as teenagers they grew up playing," he said.
(editing by Stephen Addison)