Police in Paris have arrested a teenager believed to have been behind a false security alert at a church over the weekend that triggered a major police operation, a judicial source has said.

More than 100 police officers, including elite units, rushed to the capital's busy Chatelet shopping district on Saturday after a call that claimed hostages had been taken inside the Saint Leu church.

Deadly attacks by Islamist militants – including bombings and shootings in Paris which killed 130 people last November, and, in July, a truck attack in Nice killing more than 80 and the murder of French priest Jacques Hamel in his Normandy church – have raised tensions between communities in France.

"In these tense times, those who come up with these sick jokes...deserve to be punished severely," Prime Minister Manuel Valls told reporters.

French weekly L'Obs on Sunday said on its website that it had made contact with two teenagers believed to be 16 and 17-year-olds, who played the news magazine a tape of what they said was their call to the police.

"The initial idea was to 'swat' a mosque, but after Saint-Etienne-du-Rouvray we figured it would work better if we targeted a church," the pair said, referring to the town in Normandy where two would-be jihadists murdered the priest.

The act of "swatting" involves deceiving the security forces into deploying emergency teams by raising a false alarm.

The latest incident came as a new poll in France showed that 29 per cent of French Muslims favour sharia law to the secular laws of the Republic.

Asked if they considered the Islamic legal and moral code of sharia to be more important than the French Republic's laws, 29 per cent of respondents answered "yes".

The poll found that 20 per cent of male Muslim respondents and 28 percent of female Muslim respondents were in favour of the face veil, the niqab, and the burqa.

Meanwhile, 60 per cent said they were in favour of letting girls and women wear a head scarf at schools and universities, which is forbidden at France's secular public institutions.

Additional reporting by Reuters.