An elite squad made up entirely of female Kurdish-trained Yazidi forces is aiming to fight on the front lines to avenge the honour of women killed by the Islamic State (Isis).

"We have not forgotten those Yazidi women sold in the slave markets of Mosul or burnt alive," the Sinjar Women's Units (YJS) commanders said in a statement.

"We know that the people Isis holds ... are waiting for us to rescue them. We will not stop until we liberate our women and take revenge."

The YJS was trained by the Kurdistan Workers' Party (PKK) forces in 2015 to reinforce the Kurdish Peshmerga and male Yazidi militia (YBS) battalions against Isis around Sinjar to retake the town.

The units are now concentrating on repulsing Isis from southern Sinjar province and the strategic town of Tal Afar, according to military sources. Around 5,000 people lost their lives when Islamic militants took Sinjar.

Survivors recounted terrifying stories of being sold as sex slaves, torture and public executions if enslaved women fought against marrying Isis fighters or refused to convert to Sunni Islam.

READ MORE: Latest dramatic photos of the battle to reclaim Mosul from Islamic State

Photographer Alfred Yaghobzadeh who travelled to Sinjar to photograph the Yazidi female fighterssaid in a Guardian interview: "There is nobody else like them." He added: "They are fighting Isis! Even America, I'm sorry, is bullsh****ng – is going there and throwing three bombs: poof.

"And they will be in their uniform until they get what they want – independence," Yaghobzadeh said. This sense of resilience and retribution becomes even more revolutionary in a military context: "For Isis it's a haram. If you're killed by a woman, you don't go to paradise."

The Sinjar Resistance Units (YBS) and Sinjar Women's Units (YBS) have also offered to fight in Mosul if invited to by the Iraqis.

In the joint statement both militia groups said, "The question of which forces will participate in Mosul Operation has widely been debated recently. As the Sinjar Defence Units, we have been fighting against Isis effectively for more than two years. Shengal is an important residential area in Mosul province, and our forces are the main units that defend it. Therefore, the Mosul operation and the governance of the city after its liberation are of utmost importance to us."

They added: "We are acknowledged and accepted by the central government in Iraq, and we are calling upon the Iraqi government to make its stance clear to all parties and officially invite us to join the Mosul operation."