ST. CATHARINES, Ont. -- Police say a man in St. Catharines, Ont., has been charged after two teenage girls were allegedly sexually assaulted and then followed to their school and intimidated.

Investigators say the girls -- both under the age of 16 -- were taken to hotels in the Niagara area over the course of several months and coerced into having sex with a man.

Police say the male suspect, who also tried to get his associates to join, then intimidated the girls by showing up at their school and other locations.

Two men were arrested Friday while driving in St. Catharines and allegedly found with drugs and cash.

Ahmad Bille, 23, is charged with nine counts each of sexual assault and sexual interference and two counts each of invitation to sexual touching and extortion.

Bille is also charged, along with Ahmed Mohamed, with possession for the purpose of trafficking.

Const. Derek Watson says Bille is being held in custody pending a court appearance scheduled for Saturday.

He says Mohamed was released from custody and is set to appear in court in January.

Watson says the police investigation began early this month.