Around 200 children fell ill on Tuesday after inhaling a toxic gas emitted from a sugar mill located close to school premises in northern Indian state of Uttar Pradesh, police said.

The students were immediately hospitalised after they complained of stomach ache, nausea and burning eyes.

The gas leak took place in Shamli district.

“Due to gas leakage today, 200 children of Shamli school fell sick but 175 have been discharged from the hospital,” a police official at state police control room said.

“At present, 23 children are in hospital and two have been referred to Panipat for specialised treatment.”

Local media reports put the number of children falling ill at around 300.

The government has ordered a probe into the incident and ordered Shamli district magistrate to ensure there remains no lapse in the treatment of the children affected by gas leak.

In May this year, around 200 students from a government-run school in Indian capital city were hospitalised following a gas leak from a container in the vicinity.