B.C.'s police watchdog is investigating after a dramatic and bizarre incident that started with a supervised parental visit in Chilliwack and ended in the death of a father after RCMP officers used a Taser on him Saturday afternoon.

The father, 43, allegedly attempted to abduct his daughter from a supervised visitation site near Vedder and Well roads. Police say he attempted to flee on foot with the girl.

Witnesses tell CTV News that the father had the girl in his arms and was weaving through traffic on busy Vedder Road.

"He was carrying her like a bear hug, like this, and he was running and frantic and screaming and running in front of cars," said Taylor Smith. "He almost got hit."

Smith, who saw what was happening from the rearview mirror of her truck, sensed something was amiss. She used her vehicle to try and block the man from running further before jumping out to help.

"If that was my little girl, somebody better be getting out to help her," Smith said.

She said another man had already reached the father and was trying to talk to him. Smith and the man wrestled with the father to get the girl away from him.

"He's going to kill her, that's what I was thinking in my head," Smith said.

She said the father made it several city blocks before they subdued him.

Once Smith and the other man separated the father and daughter, and the father took off running. The man chased after him.

Smith then turned the girl around and asked her if she was okay. The girl knew her mother's phone number and Smith said she tried calling it.

Meanwhile, Chilliwack RCMP officers caught up to the fleeing father. According to police, he was resisting their attempts to bring him into custody.

At some point, an officer deployed a Taser. Soon after, the father went into medical distress.

Officers began resuscitation efforts until an ambulance arrived, but he was pronounced dead once he reached the hospital.

"It was tragic to watch," witness Margie Walker told CTV News. "My heart cries for his little daughter."

The young daughter was physically unharmed and reunited with her mother at the scene, police say.

"This is going to be a very difficult situation for many people," said Ron MacDonald, the chief civilian director of the Independent Investigations Office.

"The family of the deceased, the young girl, witnesses. It's not something anybody ever wants to see occur."

The father's cause of death has not yet been determined, but an autopsy including a toxicology report will be conducted later in the week. The IIO is focusing on six officers in their investigation and already has several police and civilian witnesses in the case.

They're asking anyone with video of the event to come forward.

The IIO looks into every death involving police and will try to determine whether a criminal offence occurred.

With files from CTV Vancouver's Sarah MacDonald