LONDON, ONT. -- Warning: This story contains details some readers may find disturbing.

On Sunday night, around 8:30 p.m., a taxi driver pulled into the Cherryhill Mall parking lot in London, Ont., for what he thought was going to be a quick break.

He had no idea that within minutes, he would be coming face-to-face with the suspect who allegedly rammed a vehicle into a Muslim family on purpose, killing all but a 9-year-old boy in what police believe was a targeted, hate-motivated attack.

Hasan Savehilaghi, president of Yellow London Taxi, shared with CTV National News the chilling details of the encounter between the suspect and his colleague.

“He's shaken,” Savehilaghi said. “He's terrified.”

The suspect pulled up behind the taxi driver in a pick-up truck, hurling profanities, according to the witness. He was dressed in a military-style helmet and what appeared to be an armoured vest.

“He told my colleague, ‘Call police, I killed somebody,’” Savehilaghi said. “At that second, my colleague realized the front of the vehicle is severely damaged, with a lot of blood on it.”

The taxi driver called 911 and waved down a police cruiser. After police were on the scene, they quickly apprehended the driver of the truck.

“They took the vest off of him, and my colleague mentioned that the person had a swastika on his chest and back on his shirt,” Savehilaghi said.

Perhaps most chilling -- the suspect, 20-year-old Nathaniel Veltman, was laughing, he said.

Salman Afzaal, 46, his wife Mediha Salman, 44, their 15-year-old daughter Yumna and her grandmother Talat Afzaal, 74, were killed Sunday evening by a pick-up truck while they were out for a walk along Hyde Park Road.

The remaining survivor, the couple’s nine-year-old son, is in hospital with serious, but non-life-threatening injuries.

"There is evidence that this was a planned, premeditated act and that the family was targeted because of their Muslim faith," Det.-Insp. Paul Waight said during a briefing on Monday.

The National Council of Canadian Muslims (NCCM) called it a terror attack in a statement.

“A man allegedly got in his car, saw a Muslim family walking down the street, and made the decision that they do not deserve to live. He did not know them. This is a terrorist attack on Canadian soil and should be treated as such,” said Mustafa Farooq, the chief executive of the association.

Records show Veltman purchased a truck at a London dealership on May 12.

“It was a normal transaction,” Kai Idris, general manager of Southwest Auto Group, told CTV News. “I’m completely saddened by this.”

Veltman will appear in court tomorrow morning. He is facing charges of four counts of first degree murder, and one count of attempted murder.  

If you need mental health help in the wake of the London, Ont. vehicle attack, support and resources are available here.