Rostam told the Voice of America (VOA) , December 5, the group is called Jundullah and they consist of about 200 militants.
Jundullah is believed to active in the areas between the control of the Peshmerga and the Iraqi army.
"Daesh [ISIS] militants have grown in the area and are now carrying out more attacks to prove their existence,” Rostam said.
The Peshmerga commander also said a close relative of slain ISIS leader Abubakr al-Baghdadi has been brought to the area and effected many changes in ISIS militants’ battalions.
"Baghdadi’s relative has told the ISIS militants if they don’t carry out attacks they will be questioned,” he added.
ISIS militants have carried out continuous attacks over the last few days in areas disputed between the federal Iraqi government and the Kurdistan Regional Government (KRG), most recently in the Diyala and Kirkuk governorates.
The public relations head of the Patriotic Union of Kurdistan (PUK) in Kirkuk announced that two Peshmerga forces were killed and two others were wounded in an ISIS attack on Peshmerga positions in an areas in the Kurdish-majority province of Kirkuk.
Nejat Haji Tawfiq, the head of PUK public relations organization in Kirkuk, said in an interview with the party's official website that ISIS elements had attacked the positions of the Kurdistan Region Peshmerga forces in the Goli Qara Salem heights in Sheikh Bazini area of ​​Kirkuk province late on Sunday.
The attacked region is among the disputed areas between Erbil and Baghdad that both claim authority over.
He added that fierce clashes broke out between ISIS elements and Peshmerga forces following the attack, in which one officer and a Peshmerga force were killed and two other Peshmerga were injured.
He also noted that ISIS elements in the attack used the tactics and plans they applied in their recent attacks in Makhmur and Kulajo. This is the second time in recent days that ISIS elements have attacked the disputed areas between Erbil and Baghdad.
It should be noted that Kurdistan Regional Government officials emphasize that the distance between Peshmerga and Iraqi Army positions in the disputed areas has created a security vacuum and made opportunities for the ISIS movements which the group uses to conduct its attacks.
In recent months, a series of lengthy talks have been held between Kurdistan Regional Government (KRG) military officials and the Iraqi central government on bilateral cooperation to counter ISIS's growing movements in the disputed areas between Erbil and Baghdad
The two governments had previously announced that they reached an agreement on joint operations and coordination to fill this security gap, and two joint forces will be formed for this purpose and six joint coordination centers will be established in this regard.
Jabar Yawar, secretary general of the Ministry of Peshmerga, emphasizes that the failure to implement the previous agreements between Erbil and Baghdad is a major factor in the increase of the recent ISIS activities and attacks.
Attacks from ISIS militants have been a nightly occurrence over the past several days in areas disputed between the Kurdistan Regional Government (KRG) and Iraq.
Villagers responded to an ISIS attack in the village of Liheban in Kirkuk’s Sargaran sub-district on Saturday, December 4, night and the village was later evacuated.
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