PARIS (AFP) - Three young French women are facing possible jail time and heavy fines for making nearly 1,000 prank calls to Paris firefighters over more than a year, police said.

The calls, made between February 2011 and September 2012, included insults to firefighters, incoherent babbling and false reports of emergencies, the Paris police prefecture said.

Four of the calls resulted in firefighters wasting time by responding to false alarms.

Police eventually tracked the calls to two sisters, aged 17 and 20, and their 16-year-old friend.

The three admitted to making the calls, police said, and are due to appear in court for sentencing.

They each face up to two years in prison and a 30,000 euro (S$48,300) fine for the false alarms.