NORTH BATTLEFORD, Sask. -- The afternoon Colten Boushie was killed, police say Gerald Stanley was at home with his son Sheldon when the two heard an SUV drive into his Saskatchewan farmyard.

They told police they heard someone get into the family's pickup truck and then get back into the SUV. Sheldon Stanley said he heard the family's quad start up.

What allegedly happened next is contained in information the RCMP submitted to court to obtain a search warrant for the Stanley farm near Biggar, west of Saskatoon, after 22-year-old Boushie died from a gunshot to the head.

None of the information has been tested in court and Gerald Stanley, who has been charged with second-degree murder, has pleaded not guilty.

The document says the father and son called police and yelled at one of several passengers, who jumped back into the SUV. They told police the vehicle began to drive off before it swerved at them.

Sheldon Stanley, who was carrying a hammer because he'd been helping his dad build a fence, told police he hit the windshield of the SUV. Gerald Stanley kicked the tail lights, the document says.

Police believe the SUV hit another vehicle parked in the farmyard and came to a stop, before the driver and a passenger took off.

Sheldon Stanley said he went inside to get truck keys and heard two gunshots. When he stepped back outside, he heard another shot.

He told police he saw his father "who looked sick, with a gun in his hand." Sheldon Stanley said his father told him that he did not know what happened, "that the gun just went off, and he was trying to scare them."

In his own statement to police, Gerald Stanley said he went into his shop, got his handgun and put bullets in the magazine. Stanley said he shot two rounds into the air to scare the group away.

The document says Gerald Stanley agreed when the officer interviewing him said Stanley "went up to the driver's side window and shot the male driver once in the head and killed him."

Stanley is free on bail. His lawyer, Scott Spencer, did not respond to requests for comment. But in a statement to the Globe and Mail he said the document "reflects the RCMP's earliest theory of the case and is of course not admissible evidence."

"I encourage all to respect the judicial process and reserve judgment until all evidence is presented, and tested, in open court," the Globe quoted the lawyer as saying. "To do otherwise will only compound the tragedy that has occurred and cause further pain to the Boushie family at the expense of Gerald's right to a fair trial. Now is not the time to cast stones or refuel the sometimes destructive debate that this incident generated."

Boushie's killing in August ignited racial tension in Saskatchewan.

First Nations leaders accused the RCMP of bias because their initial news release about the shooting said people in the car were taken into custody as part of a theft investigation. They were released without charges.

Some said Boushie wouldn't have been shot had he not been indigenous.

Others supported vigilante justice. One widely circulated screen grab from a Saskatchewan farmers group on Facebook said that Stanley's only mistake was leaving witnesses.

Eric Meechance, who was in the SUV that afternoon, told police he heard two gunshots, which he believed were fired at him because he could hear "the bullets buzzing by him, and then he heard a third shot."

Police say Boushie was pulled from the vehicle by his girlfriend, Kiora Wuttunee, and another girl.

Wuttunee said she'd been sleeping in the back seat with Boushie beside her. Wuttunee said she woke to see Meechance and Cassidy Wuttunee, another friend, running from the SUV. She said Boushie jumped into the driver's seat, but the SUV wouldn't move. It had a flat tire from earlier in the day.

In an interview after the shooting, Meechance told The Canadian Press the group was heading home to the Red Pheasant First Nation after an afternoon of swimming when they got a flat tire and were looking for help.

In the court document, Kiora Wuttunee is quoted as telling police she saw a guy wearing sunglasses walk up and shoot Boushie in the head without saying anything.

Sheldon Stanley told police he saw the barrel of a gun without a stock on the floor of the SUV after Boushie's body fell out.

Police say in the document that they also got a call about an attempted theft at a neighbouring farm a few minutes before the shooting. The neighbour, Glennis Fouhy, reported that a black SUV came into her yard, and someone from that vehicle went through her car's glove box and console.

The Fouhy family also said someone had gone through two trucks on their property. Fouhy's son, Murray, told police the vehicle that came into their yard must have had a flat tire because of the tracks he saw.

Police later found a broken wooden stock from a rifle near one of the trucks on the Fouhy farm.

Police say in the court document that they believe the rifle stock is from the gun barrel found in the SUV.

Stanley is due back in court for a preliminary hearing in January.