Police had contact with the suspect a day before he got behind the wheel of an SUV and drove it into the crowd at a Filipino festival in Vancouver, killing 11 people, authorities said Monday.

A driver plowed a car into a crowd at a street festival celebrating Filipino heritage in Vancouver on Saturday night, killing at least 11 people and injuring dozens more in what police are calling “the darkest day” in the city’s history.

A 30-year-old Vancouver man was arrested at the scene and the department’s Major Crime Section is overseeing the investigation, police said.