Islamic State fighters may be taking cocaine to boost morale as Coalition planes bomb them from above, and Kurds advance on their territory.

Kurdish fighters uncovered a bag of cocaine at the home of IS leader, Emir Abu Zahra, after killing him in a military operation deep inside the war-torn city of Kobane in Syria.

The discovery in the Botan neighbourhood suggests widespread drug use within ISIS which is very much against the doctrines and principles of Islam.

They believe Zahra distributed the drug among his fighters to boost morale - as ground assaults by Iraqi Peshmerga and bombing raids by the US Air Force begin to take their toll.

Discovery: Kurdish fighters found a bag of cocaine (pictured) from the home of an IS leader, Abu Zahra

Drugged: The Kurdish soldiers believe Zahra was distributing the drug to up to 40 of his fighters

Forbidden: The use of narcotics goes against the doctrines and principles of Islam

Raid: Abu Zahra was killed in the military operation which uncovered the bag of cocaine and an armoured laptop (pictured)

Islamic State's propaganda videos have previously shown the extremist group whipping three drug addicts near the Syrian city of Damascus.

The captions on the video being circulated suggested the men were being punished for taking illegal substances, in accordance with Sharia Law.

Islamic State's religious police, known as the Hesbah, have previously been pictured burning a large supply of cigarettes near the IS-controlled city of Raqqa.

While amateur footage online shows its soldiers burning fields of what appears to be a marijuana farm.

Despite the image they portray, there have been constant rumours of drug use within Islamic State ranks.

The group's leaders are believed to drug their fighters so they fight more bravely, although their enemies suggest this inspires reckless and ineffective attacks.

Kurdish fighters have reportedly found mysterious pills, capsules and syringes on both dead and alive IS fighters.

High-tech: An armoured laptop worth over £2,000 was also recovered from Abu Zahra's house

Operation: A dozen Kurdish fighters from the People's Protection Units (YPG) carried out the raid on Zahra's home

Destruction: The city of Kobane (pictured) has been reduced to rubble after continuous fighting between Kurdish, regime, and ISIS forces

The dozen soldiers from the People's Protection Units (YPG), who carried out the raid on Zahra's home, also found an armoured Dell Latitude XFR laptop, which costs over £2,000.

Kobane, on the northern border between Syria and Turkey, has been the scene of intense fighting between Kurdish and IS forces.

Kurdish fighters have made great advances into IS territory in Kobane sine the new year, thanks to aerial support from the US Air Force and artillery fire from Iraqi Pehmerga soldiers.

ISIS were pushed back in the south and south-east, and retreated from both the Cultural Centre and the governmental square.