A coffee shop owner who displayed a "Je Suis Charlie" sign outside his café was left terrified when a man stormed his shop saying those "people deserve to be killed".

Adel Defilaux, 32, a French-born Muslim, put the sign up outside The Antishop in Brick Lane, London as a gesture of solidarity towards France following the Paris attacks last week which killed 12 Charlie Hebdo staff – including four of its prominent cartoonists.

But on Tuesday (13 January) at 9.30am Defilaux was threatened by a passer-by who entered his premises demanding that he take it down.

"I asked him why and he said his community was offended by it and said if I didn't remove it something bad was going to happen," Defilaux told the Evening Standard.

"I told him I was Muslim myself and I wanted to talk gently with him and I said people can't kill journalists for expressing themselves.

"I calmly explained to him that what he was saying was not the reality of Islam. I thought I could calm him down, but it had the opposite effect. He went crazy.

"He said 'I believe these people deserve to be killed and anyone supporting them deserves also to be killed'.

"I was all alone and started getting scared. He was a dangerous person. He said if I didn't take down the sign he would smash up the shop, and then he just left."

Defilaux said he had not received any other complaints about the sign.

"These fanatics believe in the wrong stories and have no shame in attacking people," he added.

The intruder is described as Asian, in his thirties, and wearing a grey sweater, scarf and blue jeans.

Police were investigating the incident and today (14 January) surveying CCTV footage.