The couple had married 30 years ago in Afghanistan, and the marriage had been kept secret since their arrival in Canada.

The family, originally from Kabul, spent 15 years in Dubai before moving two years ago to Montreal.

Initially, Shafia had told police that the deaths occurred as the family was headed home after vacationing in Niagara Falls and had stopped for the night at a Kingston hotel.

Shafia said the family was travelling in two cars and that he awoke to find one car missing. He reported the car missing to police, and said his oldest daughter, Zainab, was known to take the family car without permission or a licence.

Police said their investigation proved that in fact all three accused had operated the vehicle that wound up in the canal.

Police held a moment of silence for the victims at the beginning of the emotionally charged news conference.

'All shared the rights within our great country to live without fear, to enjoy safety and freedom ... and yet had their lives cut short by members of their own family,' said Tanner.

Shafia and Yehya have three more children, two daughters and a son, now under the care of youth protection authorities in Montreal.

No court date has been set yet.