OTTAWA -- An Ottawa man has been charged in an alleged sexual assault at a cemetery.

Police say a woman agreed to meet a man she didn't know at Beechwood Cemetery in the city's east end Friday afternoon.

They say the woman reported he then sexually assaulted her at knife-point.

Police say another woman witnessed the incident and alerted others, who then called police and detained the man until officers arrived.

Investigators say the witness left the area before officers could speak with her, and they're asking her to come forward.

Eric Richards, 40, is charged with sexual assault with a weapon, forcible confinement, dangerous driving, uttering a death threat and mischief over $5,000.