Ottawa police are warning people to be vigilant after a 29-year-old man was charged with multiple offences, including sexual assault and forcible confinement, in connection with four incidents involving young women in the Byward Market.

Police say the incidents occurred between March 19 and May 1, and involved young women between the ages of 19 and 22.

In each case, the victims were allegedly approached and offered a ride home after a night of drinking in the Byward Market.

Police say some of the victims had their cellphones stolen; some were allegedly sexually assaulted.

Magabi Lashury Suleiman, of Ottawa, was arrested on Monday. He is charged with two counts of sexual assault, three counts of forcible confinement, four counts of theft under $5,000, three counts of breach of recognizance, one count of theft of a credit card, one count of criminal harassment and one count of intimidation.

Ottawa police Staff-Sgt. John McGetrick says it's easy to forget there's a risk when you're out on the town. He says the case is a good reminder of how important it is to be cautious.

"Be vigilant of your surroundings and stay with a group and just be aware. Sometimes if you're out drinking and having fun for some people it can reduce their ability to be vigilant. We just want to make sure folks are safe," McGetrick told CTV Ottawa.

Anyone with information about the case is asked to contact Ottawa police at 613-236-1222, ext. 5944 or Crime Stoppers at 613-233-8477 (TIPS).