Saint John police are investigating an arson Friday night at Shamrock Park.

Saint John police and fire officials are investigating a suspicious fire at Shamrock Park in the city’s north end.

Around 9:45 p.m. Friday a patrol officer noticed heavy smoke coming from the field house at the park. The building houses change rooms and a canteen.

Firefighters were called and brought the blaze under control.

"The fire was contained rather quickly," police Sgt. Greg Oram said.

Police say the fire is suspicious. They are asking for anyone with information about it to call police or Crime Stoppers.