The air bombardment, which took place on Thursday, is believed to have degraded the chemical weapons capabilities of "Islamic State" in Iraq, Pentagon spokesman Peter Cook said in a statement.

The strikes were conducted following crucial information from a captured senior insurgent, he added.

Sulayman Dawud al-Bakkar, the militant group's head of chemical and traditional weapons manufacturing, was detained by US-led coalition forces in February.

"We believe that the information we've been able to obtain will allow us to conduct additional operations," Cook told a news briefing, adding that the intelligence came from "information we learned from this individual."

Al-Bakkar gave details about IS' chemical weapons facilities and production and the people involved, Cook said.

The CIA is concerned the militant group has the ability to produce the toxic arms, which are widely considered to be weapons of mass destruction.

IS targets disrupted

"The information has resulted in multiple coalition airstrikes that have disrupted and degraded IS' ability to produce chemical weapons and will continue to inform our operations in the future," added Cook.

Al-Bakkar, also known as Abu Dawud, was a former chemical and biological weapons expert under Saddam Hussein's regime. Iraqi intelligence officials said he is about 50 years old.

He has since been turned over to the Iraqi government.

Cook said the US does not believe it has been able to eliminate all of IS' chemical weapons capability.

US intelligence officials believe IS jihadis have carried out at least 12 mustard gas attacks and three others are likely. The attacks have resulted in deaths, but were a result of the artillery shells, not the gas itself.

Germany's Defense Ministry has also claimed that the militant group has used chemical weapons on Kurdish peshmerga.

mm/sms (AFP, AP, dpa, Reuters)