The teenage suspect in a mass shooting in rural British Columbia had been the subject of a number of police visits in recent years because of mental health issues, authorities say. Police say the 18-year-old - who was found dead on the scene from a self-inflicted gunshot wound - killed eight people, including six children, in Tuesday's attack in Tumbler Ridge. Jesse Van Rootselaar had previously been apprehended and assessed under the Mental Health Act, and used to have a firearms licence. It is unclear who owned the guns used in the attack, or what was the motive. Prime Minister Mark Carney has said he will visit the mountain town in the coming days. British Columbia, in western Canada, proclaimed Thursday a day of mourning across the province. Five students aged 12 to 13 and a 39-year-old teacher were killed and at least 25 others were injured at Tumbler Ridge Secondary School. Two others - the suspect's mother, also 39, and 11-year-old step-brother - were found dead at a nearby home, where the attack began. Tumbler Ridge has about 2,400 residents, and its secondary school, where the shooting unfolded, has 160 students. The RCMP also said there had been guns in the suspect's home, which had been seized by police about two years ago. Someone in the family later successfully petitioned to get the firearms back.