12 DEAD IN PARIS MASSACRE: Islamic gunmen execute French police officer as he pleads for his life after terror attack on satirical newspaper Charlie Hebdo at centre of Mohammed cartoon storm

Twelve people were killed today when gunmen carried out a 'massacre' at the offices of a notoriously anti-Islamist newspaper in Paris - including a police officer who was executed as he begged for mercy on the pavement.

Three masked attackers brandishing Kalashnikovs burst into the Charlie Hebdo headquarters, opening fire on staff after seeking out journalists by name.

Those executed included four of the most famous cartoonists in France – men who had regularly satirised Islam and the Prophet Mohammed – including the newspaper's editor-in-chief, Stephane Charbonnier.

Witnesses said the suspect Al Qaeda killers were heard to shout 'the Prophet has been avenged' and 'Allahu akbar!' as they stalked the building.

Horrific footage also emerged showing an injured police officer slumped on the pavement outside the office as two of the gunmen approach.

In an apparent desperate plea for his life, the officer is seen slowly raising his hand towards one of the attackers, who responds by callously shooting him in the head at point-blank range. 

Despite a shoot-out with armed officers, the 'calm and highly disciplined' men who reportedly spoke perfect French were able to escape in a hijacked car and remain on the loose. 

Brutal execution: A police officer pleads for mercy on the pavement in Paris before being shot in the head by masked gunmen during an attack on the headquarters of the French satirical publication Charlie Hebdo, a notoriously anti-Islamic publication

A young mother and cartoonist who survived the massacre today told how she had let the suspected Al Qaeda killers into the office.

Corrine Rey said she had returned from picking up her young daughter from a kindergarten when she was confronted by two heavily armed men wearing balaclavas.

'I had gone to pick up my daughter at day care, arriving in front of the building, where two masked and armed men brutally threatened us,' said Ms Rey, who draws under the name 'Coco'.

'They said they wanted to go up to the offices, so I tapped in the code,' said Ms Rey, referring to the digi-code security system on the interphone.

Ms Rey and her daughter hid under a desk, from where they say two other cartoonists being executed. 'They shot Wolinski and Cabu,' she said. 'It lasted five minutes. I had taken refuge under a desk.'

Ms Rey said the men 'spoke French perfectly' and 'claimed they were 'Al Qaeda terrorists'. 

Gunmen reportedly told another witness: 'You say to the media, it was Al Qaeda in Yemen.' 

Meanwhile, there were reports of a car explosion outside a synagogue in Sarcelles, a commune in the northern suburbs of Paris, just hours after the Charlie Hebdo attack. 

Daily Mail