French police are hunting for thieves who stole bronze bells from the steeples of listed churches in Provence in the dead of night over the past month.

Residents of Ginasservis, Brue-Auriac, and Esparron-de-Pallieres have been left dumbfounded by the disappearance of their churches’ chimes.

The first to be targeted was Ginasservis, a town of 1,800 people 50 miles north-east of Marseille, where two bronze bells weighing 50-80kg each, one dating from 1737 and the other from 1867, were stolen from two different churches on 21 July.

The thieves had to cross a graveyard to reach one of the chapels, Le Parisien newspaper reported. In the process of taking down the bells they damaged the roof of the church.

On 10 August, thieves struck again, this time 15 miles away in Brue-Auriac, where they made off with a bell weighing 85kg from a 12th-century Romanesque church.

“The chapel is outside the centre of the village, which is probably why it was targeted,” said the town’s mayor, Andre Rousselet. He said the bell had probably been melted down as its engravings, including the seal of the bell foundry, would make it difficult to sell on.

Last week it was the turn of the nearby hamlet of Esparron-de-Pallieres, where another listed 12th-century Romanesque church, on a hillside among ancient oak trees, was left bereft of its treasured 50kg bell.

The only trace of the thieves’ presence was the roof tiles found scattered on the ground.

The public prosecutor leading the investigation into the three incidents said it was still unclear if the robberies were linked.

“We take this very seriously. Either the bells are being sold on or they are being melted down for the bronze,” said the prosecutor, Pierre Arpaia.

Le Parisien cited a source familiar with the traffic of stolen goods as saying there was a thriving black market for old church bells, which can fetch up to €20,000 (£18,000) a piece among collectors of old artworks or religious artefacts.

Catholic authorities in the Var diocese, where the churches are located, have told worshippers to be on their guard.

“What more can we do?” one priest told Le Parisien, adding that all parishioners could do was pray.