Iraqi activist group Mosul Eye says the ISIS Shar'ia Board issued a savage "oral fatwa (an Islamic term for a religious decree)" to its members authorising them to "kill newborn babies with Down's Syndrome and congenital deformities and disabled children".

If true - and reports from the war-torn region are difficult to verify - it means ISIS has taken a leaf from the Nazis, who murdered disabled children it perceived to be a "burden on the state".

Mosul Eye monitored the deaths of children with Down's Syndrome and other congenital deformities and discovered the fatwa was issued by one of Islamic States's Shar'ia judges, a Saudi judge named " Abu Said Aljazrawi.

ISIS issues fatwa to kill all children with Down's Syndrome

Their information indicates that most of the children born with Down's Syndrome are those of foreign fighters who married Iraqi, Syrian and Asian women.

The activists recorded more than 38 confirmed cases of killing babies with congenital deformities and Down's Syndrome, aged between one week to three months. They were killed by either lethal injection or suffocation.

Some of those killings took place in Syria and Mosul.

ISIS issues fatwa to kill all children with Down's Syndrome

A statement from the activist group said: "As if it is not enough for ISIL (another name for ISIS) to kill men, women and the elderly, and now, they kill children."

One Facebook user said: "I have just shed tears for these babies. I have two children with special needs, my heart is breaking.

"They are worse than the Nazis."