Isis Libya
Isis in LibyaISIS Media

Islamic State fighters in Libya have reportedly acquired large quantities of deadly mustard gas and nerve agent sarin from an abandoned factory.

The Libyan military said the ISIS militants now have tons of deadly chemical weapons belonging to the Gaddafi regime.

"Before his death, Gaddafi left approximately 1,000 cubic tons worth of material used for manufacturing chemical weapons and about 20,000 cubic tons of mustard gas," a Libyan military official told the London daily, Asharq al-Awsat.

The chemical weapons have now fallen in the hands of the Islamic State fighters as the militia group knew their location, he added.

It has also been reported that the terrorist group fighters have now begun testing the deadly chemical weapons near Tripoli.

Former British Army officer Hamish de Bretton-Gordon told The Daily Mail on Sunday that although the weapons are more than a decade old and may have degraded, they still pose danger.

"While we don't know how much Isis has acquired, and though the Libyan Sarin dates back to the Gaddafi era, it would still have a toxicity and pose a danger," he said.

"Libya is virtually Europe and so the fear factor from a European perspective is huge. I should think the security forces will be watching this situation very closely."

ISIS is reported to have used chemical weapons, including chlorine in Iraq and Syria.