Charlie Hebdo France police step up security
France has tightened security after deadly attacks in Paris in November that left 129 people deadReuters

Four people suspected of planning an "imminent" attack in central Paris have been arrested by French police, according to local media.

The plan was foiled by French police, who detained the three men and a woman, said reports. According to TF1, the four were already known to authorities as being suspected radical Islamists. It was reported two were French brothers of Turkish origin and authorities believed the group posed an "imminent" danger.

During a search this morning (16 March), investigators found a cartridge for an assault rifle, electronic material, USB sticks and a safe, TF1 said.

In November, French Prime Minister Manuel Valls warned that the country may come under attack by terrorists using chemical or biological weapons. His speech came as MPs gathered to vote on whether to extend emergency measures introduced following the Paris terror attacks on 13 November.

Speaking to the French parliament in the wake of bomb and gun attacks in the French capital that killed 129 people, Valls called on representatives to extend the country's state of emergency measures. "We must not rule anything out. I say it with all the precautions needed. But we know and bear in mind that there is also a risk of chemical or bacteriological weapons," said Valls.