Increasing concern about possible militant attacks on civilians in Europe has led to Japan becoming the latest country to issue a warning for its citizens living or travelling on the continent.
It is a highly unusual step and follows threat alerts by Britain and the US, in the wake of intelligence reports.
The UK has updated its travel advice for Europe, warning now of the “high threat” of attacks, particularly in Germany and France.
Security services have warned of an al-Qaeda plans to send teams of gunmen into crowded places to kill civilians, like in Mumbai in 2008.
“I wouldn’t imagine that a statement like this would’ve been done in a flaky way. This will have some kind of root in either an intelligence picture or on the back of what happened last week and the announcement last week that there was a thwarted attack in Europe and the UK. So, on that basis, we should take it seriously.” said counter-terrorism expert Andy Hayman.
France is on high alert, just one step under its maximum level. Tourists have been evacuated from the Eiffel Tower twice in the last few weeks – and armed police patrol the streets.