Police are starting to get a clearer picture of the events that led up to the violent confrontation on a southern Alberta highway that resulted in the death of four people.

The shooting happened on Highway 2 about 1 km north of Claresholm at about 3:30 a.m. on Thursday.

A passing motorist came upon the two vehicles on the highway and called 911.

When police arrived they discovered three people dead at the scene.

A man and a woman were transported to hospital. The man died from his injuries and the woman was treated and is recovering.

Police say the gunman took his own life and was among those who died at the scene.

It is believed that the shooter was in one car and the other four people were in the second car.

The Lethbridge Bulls Baseball team has confirmed that two of the shooting victims were members of their organization.

Tanner Craswell and Mitch MacLean were both in their 20's and were from P.E.I.

The pair was in Alberta to attend the Prairie Baseball Academy in Lethbridge.

The identity of the third victim was confirmed as 21-year-old Tabitha Stepple of Lethbridge.

The lone survivor is Shayna Conway, of P.E.I, who was also shot and is recovering in hospital.

Friends told CTV News that Stepple was the target and was shot by her jealous ex-boyfriend in a fit of rage.

Friends say Stepple met Derek Jensen at a Lethbridge nightclub in 2010.

"She would tell me he's very controlling. She would say things like, I'm not allowed to do anything without him. He wants to know where I am and what I'm doing," said Claire Sullivan.

Friends say the pair apparently broke up a few months ago, but was still living together.

On Wednesday night, Stepple agreed to drive her co-worker Shayna Conway, Conway's boyfriend Tanner Craswell and a friend, Mitch MacLean to the Calgary airport.

The three were heading home for the holidays and met with friends, before they left, to celebrate Craswell's birthday.

Friends say that is when they ran into Jensen.

"Saw her and lost it, lost his mind and pushed her out of a chair and he was like yelling. 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," said Cait McFarland.

Stepple began the drive to the Calgary Airport with Conway, Craswell and MacLean at about 1:00 a.m.

A couple hours later, RCMP was called to the horrific scene along Highway 2.

Investigators now believe the gunman followed the group in his car and then opened fire on the side of the road.

Police spent most of Thursday at the scene and are confident they will determine exactly what happened.

They have spoken briefly to Conway. "Our members have had a very preliminary discussion with her. We will be getting more information from her," said RCMP Sergeant Patrick Webb. "She's gone through a horrific, horrific incident, she's almost been killed and she's had her friends killed around her."

Police say the tragedy appears to be a murder/suicide and they are not looking for anyone else in this investigation.

Autopsies are being done on the victims on Friday to confirm the cause of death.

A tribute page has been set up on facebook and friends are sharing pictures and stories about the three victims.