Iraqi authorities have launched an investigation into Saturday's armed attack in Farhatiya that left eight dead and four missing, Prime Minister Mustafa Al-Kadhimi has said.
The attack, which took place in the Salaheddin province in north-central Iraq, happened when a group of heavily armed men raided the village and kidnapped 12 men in the early hours of Saturday.
The victims, who are all believed to be relatives, were then transported to an unknown location, according to a report by the New Arab.
Eight corpses showing marks of gunshot wounds were discovered later on Saturday in an unidentified location. The fate of the final four men, however, remains unclear.
The victims were between 59 and 14-years-old and were all male.
Kadhimi visited the site of the massacre on Sunday and participated, alongside other senior officials, in a mourning ceremony for the victims.
Speaking after the reception, Kadhimi announced an investigation into the incident, saying that he would personally follow developments in the case.
The Iraqi prime minister added that the rights of the victims "will be upheld through the law" and that the perpetrators would not escape justice but be "punished by the courts".
Meanwhile, the leader of the Popular Mobilisation Front (PMF) Faleh Al-Fayyad termed the attack a "massacre" in an interview with Al-Iraqiya TV.
"All parties, first among them the Popular Mobilisation Forces, want to find those who carried out this act, and we will take all measures against those who carried out, hid, or were complicit in [the attack]," he added.
Meanwhile, relatives of the victims told the New Arab's Arabic-language service they believed the attack was carried out by Asa'ib Ahl Al-Haq militiamen, who control the area.
The militia enforce illegal tolls, direct insults at locals and frequently threaten to kidnap women, a relative of the victims was quoted as saying.
He added that complaints by Farhatiya residents to Salaheddian governorate officials over these issues could be a possible reason for the attack.
However, local Asa'ib leader and Iraqi MP, Hassan Salem, told the New Arab's Arabic service that the militia was not responsible for the assault.
Salem said political rivals were attempting to pin the blame for the massacre on him in the hope of making electoral gains.
Nevertheless, the PMF has long been accused of carrying out sectarian cleansing of the local populace in Salaheddin province through field executions, torture of prisoners until death and looting of deserted towns.