Isis fighters inside Yarmouk camp
Fund crunch forces ISIS to kill injured jihadis and sell organs. Representational Image: The Islamic State reportedly executed eight Dutch members, though a Syrian monitoring group has refuted the claims.ISIS Media/Twitter

As the Islamic State attempts to launch more attacks in Saudi Arabia, Saudi Isis fighters have now warned their own families in the kingdom that they will be killed unless they 'repent'. 

The new Isis threat to Saudi Arabia came in the form of a video on Sunday, in which militants from the kingdom threatened to kill their families 'if they do not repent', Arab News reported. 

The video shows Saudi Isis militant Jammer Al-Khamali Al-Anzi with photos of his family members and warning that they will be killed. 

Al-Anzi had been jailed in Saudi Arbia for six years and then travelled to Syria to join the Islamic State. 

The video comes just two weeks after two brothers who were Isis supporters killed their cousin, who was in the Saudi army, and recorded the gory murder on video on the day of Eid al Adha. 

One of the brothers, 18-year-old Abdul-Aziz Radi Ayash al-Anzi was shot dead by security forces while his older brother 21-year-old Saad Radi Ayash al-Anzi was arrested after a manhunt. 

The Islamic State has gained a number of supporters in the kingdom, and a recent study showed that one of the highest number of Isis-sympathising Twitter accounts outside of the group's stronghold in Iraq and Syria was in Saudi Arabia. 

Saudi fighters are also believed to constitute one of the largest groups of foreign fighters within Isis ranks. 

Last week, the Saudi Interior ministry said that two Isis cells in the kingdom had been intercepted and two Isis militants were killed. They were said to be linked to the deadly mosque bombing in August in Abha city, in which 17 people were killed

Saudi Arabia has been hit by a string of terror attacks, especially aimed at Shia mosques in the country, in recent months, which have been claimed by Isis.