Three overnight fires in Vanier are being investigated as arson and police believe they were deliberately set.

"It would be highly unlikely that you'd have three fires in such a short timeframe in such a confined area that would be accidental," says Sgt. David Christie, who's with the Ottawa Police Arson Unit.

It all started around midnight when a working fire was declared at 253 Deschamps Avenue after a witness called 911 to report heavy fire and smoke billowing from a three-storey home. It was under renovation.

Less than an hour later, firefighters were called to 209 Ste-Anne Avenue where another home was engulfed in flames.

"The flames were, I'm not kidding, 70 feet high," says neighbour Paul Jolicoeur.

Witnesses say tires on vehicles exploded and there was electrical arcing, causing multiple flashes and sounds like firecrackers.

Neighbours made sure people in the four separate units of the house got out safely. A man had to be rescued by firefighters from a second floor window. He was assessed by paramedics but wasn't taken to hospital.

The third call, just before 3:30 a.m., reported heavy smoke and fire in an abandoned restaurant at 270 Montreal Road. No one was injured in that fire.

The causes of the blazes aren't known yet, but they are similar to a separate string of fires from 2016 in the same area.

Last August, fire crews were called to Palace St. and Cyr Ave. for fires. One was at an empty house up for sale and the other was a detached garage.

Police say it's too early to make a connection, but there are similarities.

"They all appear to be set using available fuels. In other words, refuse, garbage, recycled boxes, stuff that's left out and easily accessible," says Christie.

Any witnesses or anyone with information is asked to contact the Arson Unit of the Ottawa Police.

A GofundMe page has been set up to help fire victim Cali Wood get back on her feet.