A senior Syrian military officer on Tuesday denied reports of military toxic attack on rebel-held area in Syria's northwestern province of Idlib.

"This didn't happen and will not happen, not now and not before," the military officer told Xinhua on condition of anonymity.

Earlier in the day, the Syrian Observatory for Human Rights said warplanes carried out intensive airstrikes on the rebel-held town of Khan Sheikhoun in the countryside of Idlib province, killing 58 people, mostly civilians.

The opposition accused the Syrian air force of being behind the attack.

But the senior officer, who spoke condition of anonymity, said the rebels were the ones using the toxic gas against civilians to frame the Syrian army.

Still, the officer said initial speculations indicate that a depot of chemical weapons that belongs to the rebels was blown up in Idlib.

Meanwhile, other activists said that a rocket hit the hospital that was treating the wounded of the attack were struck by airstrikes in Khan Sheikhoun.

Source: Xinhua