BRUSSELS (Reuters) – A number of the Paris attackers used two apartments and a house in Belgium as possible safe houses in the weeks in leading up to their coordinated shooting and suicide bomb assault on the French capital, investigators said on Wednesday.

Federal prosecutors said in a statement, summarizing some of their findings, that the Paris attack plotters had rented an apartment in Brussels and another in the city of Charleroi at the start of September.

They had also rented a house in the town of Auvelais, some 35 miles south of Brussels, at the start of October. All three were rented for a year, and paid in cash. The tenants gave false identities.

Investigators found DNA traces of one of the attackers, Bilal Hadfi, who blew himself up in Paris on Nov. 13, the prosecutors said.

In the Charleroi apartment they found mattresses and fingerprints of both Hadfi and Abdelhamid Abaaoud, a Belgian who had fought in Syria and was believed to be one of the plot leaders. He was killed after a siege in St Denis, near Paris, on Nov. 18.

The house in Auvelais contained several mattresses.

Investigators have also established that the Seat Leon hatchback used in the Paris attacks stopped near the suspected safe houses in Charleroi and Auvelais. Another vehicle, a BMW rented by a suspect, stopped near all three locations.

Prosecutors said last week that they had found a possible Paris attacks bomb factory in the Brussels district of Schaerbeek, with traces of explosives and handmade belts.

(Reporting By Philip Blenkinsop; Editing by Simon Cameron-Moore)