The RCMP say a man shot dead by police in a Maple Ridge home on Sunday afternoon while they were responding to a “domestic incident” was armed with a knife, and officers say they used a Taser before opening fire.

The victim has been identified by family as Kyaw “John” Din, who siblings say lived with mental illness, but who they say was not violent. 

B.C.’s police watchdog, the IIO, has been called in to investigate exactly what unfolded in the house on Colemore Street near 124 Avenue as police arrived around 1 p.m on Sunday afternoon after the family says they called them for help. 

Din’s siblings say the 55-year-old would sometimes stop taking his medication, which meant the family would have to call police to have him taken to hospital from his sister’s home. 

But they say Din did not want to go with officers on Sunday, and while his sister says she asked police to wait for other family members and a translator to arrive, she says it didn’t take long for shots to ring out in her brother’s bedroom.

“For no reason they use they bullet, for no reason. My brother was not armed, he was not violent,” Yin Yin Din said outside her home on Sunday afternoon.”

But police claim Din was armed with a knife when officers entered the home. 

“During the course of the interaction a conducted energy weapon was deployed but was not successful, and another police officer fired their gun,” the BC RCMP said in a statement.

Yin Yin Din told reporters she had met with police when they first got to the home.

"They asked me if my brother has a gun," she said. "He doesn't have a gun. He doesn't have a knife. He's just in the room and I told the police he has a glass bottle that he might throw at you. I don't want you to get hurt and I don't want the police to shoot my brother."

She said police reassured her that they wouldn't hurt him, but she was still worried.

"Police said, 'We would never shoot your brother. We deal with this kind of thing all the time,'" she said.

The IIO and forensic investigators spent hours at the home on Sunday collecting evidence and piecing together what happened as family and neighbours watched from the street. The police tape had been removed from the home by early Monday morning and the IIO says it has completed its forensic investigation.

They are now interviewing witness officers and paramedics while waiting for autopsy results. 

"We start at zero and we let the evidence lead us to the conclusion," said Ron MacDonald of IIO. "We will listen to everyone who has anything to offer in this and add it up to attempt to figure out what happened." 

With files from CTV News Vancouver's Ian Holliday and Emad Agahi