Hours before he is alleged to have shot his ex-girlfriend, three others and himself on an Alberta highway, friends say Derek Jensen went "berserk" upon running into Tabitha Stepple on Wednesday evening.
Jensen and Stepple -- who are said to have broken up a few months ago but were still living together -- crossed paths at a Lethbridge pub as she was out celebrating the birthday of 22-year-old Tanner Craswell, according to friends.
Jensen pushed his ex-girlfriend out of a chair and threatened her, according to Caitlin McFarland.
"He saw her and lost it, lost his mind ... and he was like yelling," McFarland told CTV News. "Then we left, he was phoning her, phoning her, phoning her and said to her, 'This night's not going to end well for you. I hope you know that.'"
By early Thursday morning Stepple, who was also in her early 20s, was dead alongside Craswell and Mitch Maclean, 20, on a stretch of highway in southern Alberta. Jensen was also dead, having reportedly turned his weapon on himself after the shooting spree that also wounded a fourth victim, Shayna Conway.
"Friends say he was very controlling, always telling (Stepple) what to do," reported CTV's Alberta Bureau Chief Janet Dirks.
Conway is being treated in a Calgary hospital and is expected to recover. She was interviewed on Friday by police for insight into the shocking murder-suicide.
The RCMP have not officially identified the victims or the gunman, and have so far said little about the case.
But according to reports, the victims were driving on Highway 2 north of Lethbridge when another vehicle approached and forced them off the road.
Once the vehicles slowed, the driver of the second vehicle opened fire, leading to fatal gunshot wounds that would eventually leave three dead. The gunman then took his own life.
Media reports say Jensen -- an avid hunter and skeet shooter -- was the gunmen.
MacLean and Craswell were from Prince Edward Island -- baseball players and friends who played together on the Lethbridge Bulls, a collegiate summer baseball league operating in the Prairie provinces. MacLean was named rookie of the year and Craswell was an all-star shortstop.
They were headed back to P.E.I. for the holidays, and on Thursday morning, were getting a ride to the airport from Stepple, according to friends.
"The whole PEI community is saddened," said Baseball P.E.I. president Don Leclair, who watched the young men's short careers. "It takes a bit of the joy out of Christmas because how can you be rejoicing when others are so overwhelmed with grief?"
With files from Canadian Press and CTV Atlantic's Dan Viau
