A lightning strike killed seven students and injured 30 others in a village school on Wednesday afternoon in southwest China's Chongqing municipality, said local authorities.

The lightning struck the school while children were attending class at around 4:00 p.m. on Wednesday, in a primary school in Xingye Village, Kaixian County of Chongqing, said officials.

The students were in two separate classrooms. Four of them were seriously hurt, the sources said.

All the injured are being treated in hospital, said doctors.

The seven pupils who were killed were aged 10 years to 14, said the county officials.

The county, located in a mountainous area, is prone to tragedy. A catastrophic gas blowout in December 2003 at a natural gas field in Kaixian county claimed 233 lives.