Dozens of people, mostly children were hospitalized following an alleged chlorine bomb attack by Bashar al-Assad’s army on opposition-held Idlib in northwestern Syria, medical sources said Tuesday.

"The casualties are unfortunately mostly women and children. Luckily, there have been no deaths so far," Rami Abu Zubeyda, a doctor at a field hospital in the town of Binnish, told The Anadolu Agency.

Syrian Revolution General Commission, a coalition of Syrian opposition groups, issued a statement saying that 20 people, mostly children, were hospitalized after a Syrian army helicopter allegedly dropped a chlorine bomb on the town of Binnish near the opposition-stronghold of Idlib.

The Syrian regime has used the deadly chemical gas six times in attacks spanning at least three regions during the past two weeks, opposition activists said last week.

The Syrian Network for Human Rights said Friday that all such attacks took place after the UN adopted a resolution to halt the use of chemical weapons in the country on March 6. The network said that in these attacks, seven civilians, including three children and two women, were killed and 140 others were injured.

The UN Security Council had adopted a resolution expressing deep concern that toxic chemicals were being used as a weapon in Syria. The council strongly condemned the use of any toxic chemicals, such as chlorine, and called on those who use such weapons to be held accountable.

The resolution was approved by all members except Venezuela, a non-permanent member. The resolution threatened further action under Chapter 7 of the UN Charter should chemical weapons, including chlorine, be used again.

The Syrian civil war, which entered its fifth year this month, has claimed more than 220,000 lives so far, according to the UN.