Afzal Kohistani, the man who first drew attention to the incident in 2012, was shot in Abbottabad on Wednesday, police said. He had pursued the case in which a local Muslim leader had allegedly ordered the killings of male and female wedding guests shown enjoying themselves in a video.
Precise details remain shrouded in mystery, but Kohistani had long been adamant that the women shown in the video had been murdered.
He was shot five times on a busy road and died on the spot, Abdul Aziz Afridi, a senior police official, told the AFP news agency.
Officials said on Friday that at least two arrests had been made.
“The perpetrators of this heinous crime will be brought to justice,” Shaukat Yousafzai, the provincial information minister, told AFP.
Kohistani’s murder has ignited anger in Pakistan, where rights activists have long fought against the patriarchal notion of “honour”, which remains prevalent across South Asia.
Women have been shot, stabbed, stoned, set alight and strangled for bringing “shame” on their families for everything – from refusing marriage proposals to marrying the “wrong” man, and helping friends elope.
Men can be victims too, though it is rare.
“Will be raising this shocking murder of Afzal Kohistani in parliament,” opposition leader Sherry Rehman tweeted.
Rights activists participating in a march to mark International Women’s Day on Friday condemned Kohistani’s shooting.
“This incident has brought to the focus, once again, how vulnerable those that raise their voice still are,” said Benazir Jatoi, a human rights lawyer and march organiser.
Witness protection was “almost non-existent”, she added.
“Today’s march in Islamabad will remember Afzal and other brave Pakistanis like him,” said Jatoi.
Nighat Dad, a prominent activist, tweeted: “I march because the only pursuer of 7 years old Kohistani video case Afzal Kohistani was killed hours ago.”
The wedding video emerged in 2012, showing women clapping as two men danced in the deeply conservative mountainous area of Kohistan, 175 kilometres north of the capital, Islamabad.
The men and women had allegedly been in the room together in defiance of strict tribal customs that separate men and women at weddings, though the video does not show them together.
A local Muslim leader sentenced several women and men to death on the basis of the video.
Kohistani is believed to have been related to some of the men in the video. His family was banished from Kohistan as a result.
He took the rare step of pushing the case before the media and the justice system. The Supreme Court launched a commission to investigate – but in June 2012 was told the women had never been murdered at all.
A fact-finding team met women who were purportedly those shown in the video and said they were alive.
But Kohistani insisted that the women shown to the fact-finding officials were different women, and that the death sentences had been carried out.
Three more men – Kohistani’s brothers – were later killed by a rival family. A Pakistani court convicted six of their killings in 2014.