By Agence France-Presse Pakistan police have arrested a man over the so-called "honour killings" of his two cousins who appeared in a viral video being kissed by someone, police said Thursday. The two women were shot dead last week in a northwestern district near the Afghan border, where women are subjected to strict tribal codes that limit their movement outside of the home. Muhammad Aslam, the 26-year-old first cousin of the victims, is accused of carrying out the murders. "We have arrested the main suspect and trying to recover the pistol he used", said Mohammad Nawaz Khan, who is investigating the case. Another senior officer confirmed the arrest. Police said the two victims, both in their 20s, were later gunned down in North Waziristan's remote Garyum village and buried by family members. A third woman seen in the video, recorded last year, is the wife of the suspected killer but has been safely located, police added. Two other relatives of the women have also been arrested over the killings, while the man in the video and the man who filmed it have both been arrested for indecency. Around a thousand Pakistani women are murdered in honour killings each year -- in which the victim, normally a woman, is killed by a relative for bringing shame on the family. Perpetrators have often walked free because of a legal loophole that allowed them to seek forgiveness for the crime from another family member. But the government has since passed a law that mandates life imprisonment, even if the attacker escapes capital punishment through a relative's pardon. "Antiquated and lethal notions that 'honour' resides in women's bodies and actions still prevail across Pakistan," the country's Human Rights Commission said in a statement on the case.