An Afghan immigrant couple and their son in Canada have been found guilty of the 2009 murder of three teenage girls and another woman, and handed out prison terms of at least 25 years.

The bodies of the victims, 19-year-old Zainab Shafia, 17-year-old Sahar Shafia, Geeti Shafia, 13, and Rona Amir Mohammad, 50, were found in a car submerged in a canal lock near Kingston, Ontario in June 2009. The girls' father, mother and brother, who at the time of the deaths had gone to an exaggerated public display of grief and mourning, have been found guilty of first degree murder. 

The crime was widely termed as honor killing as the young girls and their step mother Rona Amir (first wife of their father Mohammad Shafia), had defied the strict rules of their family on dressing, dating, and using the Internet. Rona Amir wanted a divorce and supported the girls in their wish to assimilate and westernize.

The teenage girls apparently wanted to have boyfriends and refused to wear hijabs and also occasionally wore 'revealing' clothes.

Judge Robert Maranger called the crimes heinous as he sentenced Mohammad Shafia, 58, his 42-year-old wife Tooba Mahommad Yahya and their 21-year-old son Hamed to 25 years in prison, and said the evidence clearly supported the charges, according to an AFP report.

The apparent reason behind these cold-blooded, shameful murders was that the four completely innocent victims offended your completely twisted concept of honor. It's a sick notion of honor that has no place in a civilized society, the judge said.

Mohammad Shafia replied: We are not criminals. We are not murderers. We didn't commit murder. This is unjust.

The victims' mother Tooba Yahya said: I am not a murderer. I am a mother.

The verdict was announced only after a four-month-long trial at which dozens of witnesses testified.

The testimonies by the witnesses in the court revealed that the two elder daughters had boyfriends and the atmosphere of the family's home was abusive and gripped by fear. It seems the victims often received death threats because their father did not approve of the girls having boyfriends.

The prosecutors argued that throughout the four-month trial, the accused portrayed the murders as accident. They further said that the victims either drowned or were made unconscious before they were put in the family's car and pushed into the water.

They argued that according to the father, the girls had damaged the family's reputation by wearing revealing cloths and telling the school officials about the scenario at home.

According to a report in Fox News, Geeti, the youngest daughter, had told her teachers that she wanted to be placed in foster care.

The prosecution presented wiretap evidence which included one conversation in which Mohammad Shafia said that his daughters betrayed us immensely.

He is also heard calling them 'whores' and calling on the devil to defecate on their graves.

However, the defense maintained that the deaths were an accident and a result of a joy ride going wrong. They said their eldest daughter Zainab took the wheel in the middle of the drive while the family was returning to Montreal from a trip to Niagara Falls, reported AFP.

Shafia and his family left Afghanistan in 1992 and have been living in Canada since 2007. In the past 15 years, they have lived in Australia, Pakistan and Dubai.

Shafia got married to Tooba Yahya because he did not have children with Rona Amir. Rona was also living with the family but if the polygamous relationship was revealed, the family could have been deported.