Iraqi officials have said they will investigate allegations that their forces used white phosphorus against areas held by the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) group in western Mosul.

“[We] cannot deny nor confirm – we are investigating into this news and will come up with a statement to clear things up for the public,” a spokesman for Iraqi Ministry of Defence Brigadier General Yahiya Rasoul told Al Jazeera.

A Kurdish TV crew was streaming live on Saturday when Iraqi forces used what look to be highly incendiary munitions.

Shortly after clips of the alleged attack were aired, Iraqi military media issued a statement threating to take legal action against media outlets publishing pictures or video of the event.

Mark Hiznay, the Associate Arms Director of Human Rights Watch, told Al Jazeera: “The pictures show artillery-delivered WP (white phosphorus) being air-burst. The video is more difficult to assess because of the angle it was shot at.”

Human rights groups including Amnesty International raised the alarm in October last year, just in advance of the Iraqi forces’ push to retake the city of Mosul from ISIL that the use of white phosphorus around the city of Mosul “could pose a deadly risk to civilians fleeing the fighting”.

Iraqi government forces retook eastern Mosul in January and began a new push on May 27 to capture the remaining ISIL-held west of the city, where about 200,000 people are trapped in harrowing conditions.