Canada shooting: Death toll in Nova Scotia rises to 22

The toll from the worst mass shooting in Canada's modern history, a 14-hour rampage over the weekend, has risen to 22 from 19, police say.

The victims include a 17-year-old, a pregnant healthcare worker and a veteran Royal Canadian Mounted Police (RCMP) officer, BBC reports.

Authorities are yet to determine a motive for the crime. Police say the gunman knew some of the victims.

The gunman, a 51-year-old man, was killed in a confrontation with police.

During the attack he wore an authentic RCMP police uniform and drove a "look-alike" police vehicle, authorities said.

Nova Scotia RCMP updated the death toll from the attack in a statement on Tuesday along with a rough timeline of the events.

Police had previously warned the number of dead could rise as they searched the 16 separate crime scenes across north and central Nova Scotia.

Their work was also slowed by the fact there were a number of fires started - about five, according to police. They had to search through the debris of those badly burnt-out homes for remains.

The full investigation is likely to take months.