When fighters from the Islamic State (IS) attacked the Yezidi communities in northern Iraq in August 2014, they took many of their victims captive. They raped, forcibly married and converted to Islam thousands of Yezidi women, using them as sex slaves. IS is still holding a significant number of them.

Displaced people from the minority Yezidi sect, fleeing violence from forces loyal to the Islamic State in Sinjar town, walk towards the Syrian border on August 11, 2014.

Family members who managed to escape have been glued to their television sets watching the Mosul military operations. They wonder what it will mean for their missing women and girls, who have already endured so much. According to the United Nations, as of August, IS still held 1,935 Yezidi women, as well as 1,864 Yezidi men. The UK-based Syrian Observatory for Human Rights has reported that IS has moved many of the women who were being held in Mosul to Syria. But a human rights worker, tracking the movements of prisoners from the Yezidi religious minority still held in IS captivity, told me this week that at least 300 Yezidi women remain inside the city. News media reported on 24 October that at least 70 Yezidi women and children have been rescued since the beginning of the operation to retake Mosul.

Yezidi families who escaped from IS in the last year told me in August that the mental health and other psychosocial support, the Kurdish regional Government, UN, aid agencies, and donors have provided in the 15 or more camps for the displaced Yezidis in Dohuk governorate has been inadequate. Now, with people caught in the middle of a huge battle, there is going to be an even greater need for these services.

The Iraqi central government and Kurdistan Regional Government (KRG) authorities, with the support of an international coalition, announced on 17 October the start of the military operations to retake Mosul, Iraq’s second largest city, which IS captured in June 2014. There are an estimated 1.2 million civilians in Mosul.

For Yezidis in Mosul who come under the control of the Iraqi authorities during or after the fighting, including women who have spent the last two years in sexual slavery, they are going to need urgent assistance to meet their basic needs and provide mental health support.

But aid workers in the nearby city of Erbil have told me that there has been no significant planning by the military forces to ensure access for aid groups to the city, once the fighting moves there or for the aftermath.

Since the beginning of the Mosul operations, Iraqi authorities have been calling on residents in and around the city to stay in their homes throughout the fighting.

Given the amount of resistance that anti-IS forces are currently encountering in the battle for villages surrounding Mosul and the likelihood that IS will put up significant resistance inside the city, there is a strong possibility that the battle for Mosul will be long.

I have asked human rights colleagues in Erbil what the military's plan is for assisting the Yezidi population inside Mosul, in the context of the military operation. They said this is a conversation that has not yet happened.

Even for the Yezidi women and children who have already been freed during the Mosul battle, it is not clear that they will have access to the emergency assistance they need, including support for the trauma they have endured. Human Rights Watch's research showed that since the Yezidis were taken captive and since some have escaped, the camps that house these displaced people have failed to supply adequate counselling and mental health support.

The anti-IS fighting force and the aid agencies working in the region urgently need to come to a basic agreement on how to provide assistance to the civilians of Mosul who are following the government’s advice and staying home. A clearer plan is needed including the provision of special healthcare services, such as post-rape care for the victims of sexual violence. All sides in the conflict need to ensure that essential humanitarian assistance can freely flow to those who need it during the fighting, and that civilians can safely find their way out of the war zones and get the help they need to deal with the hardships and trauma of the past two years.