The man RCMP say is responsible for the mass shooting in Nova Scotia attacked and forcibly restrained a woman with whom he was in a long-term relationship late Saturday night, police confirmed Friday.

RCMP said the deadly rampage started after the gunman assaulted his girlfriend in Portapique, N.S. She managed to escape, hide in the woods overnight, and survived.

The "significant assault ... could very well have been the catalyst that started the chain of events," RCMP Supt. Darren Campbell said Friday. But he said investigators are not ruling out pre-meditation.

It is just one of a number of new details that have emerged about what happened during the manhunt for Gabriel Wortman, 51, who police say began his 13-hour rampage in Portapique before travelling through other communities, killing 22 people in all.

When the woman emerged from hiding at daybreak Sunday, she shared crucial details with police — including that Wortman had a police uniform, a mock-up police cruiser, a pistol and rifles, RCMP said during Friday's update.

The victim is now recovering, which has limited her ability to meet with police.

"I would imagine we will spend more time in the future with her. She is being cooperative with us," said Campbell.

Thirteen people were killed in Portapique alone. The gunman's partner was one of two people injured who received medical treatment and survived, Campbell said. On Wednesday, RCMP said there were no victims in hospital.

Police said they killed the gunman at the gas station. (Eric Woolliscroft/CBC)

Police have said they killed the gunman at the gas station in Enfield, N.S., at 11:26 a.m. AT on Sunday .

At the time, police were advising on Twitter that he was driving a silver Chevrolet Tracker in the Milford, N.S., area.

But by that point, the suspected shooter was actually driving a Mazda 3 owned by one of his victims, Gina Goulet, who lived in nearby Shubenacadie.

It was also in Shubenacadie that the gunman shot to death Const. Heidi Stevenson, a 23-year RCMP veteran.

Police first were called to respond to reports of gunshots in the picturesque beach community of Portapique on the shores of Cobequid Bay around 10:26 p.m. on Saturday.

They discovered a grisly scene — people shot and a number of buildings burning.

A couple pays their respects at a memorial in Portapique, N.S., on Thursday. (Andrew Vaughan/The Canadian Press)

Though they initially tried to seal off two sections in Portapique, officers later realized that their suspect was not in that area, RCMP Chief Supt. Chris Leather said Wednesday.

As the morning went on, the suspected gunman travelled through several communities, including Wentworth, Glenholme, Debert and Millbrook.

The chase covered more than 100 kilometres and ended at an exit off one of the province's main highways toward Halifax.

If you are seeking mental health support during this time, here are resources available to Nova Scotians.

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