Eight newborn babies died from an infection earlier this month in a northern Chinese hospital in an incident that was apparently covered up, state media reported Thursday.

The babies died between September 5 and 15 at a hospital affiliated with Jiaotong University in the city of Xian, Xinhua said, adding initial investigations showed no link with milk powder fed to the babies as authorities battle an ongoing toxic milk crisis nationwide.

The cause of death was an hospital-acquired infection, according to Xinhua.

The government of Shaanxi province, where Xian is located, ordered the university to punish "those who tried to cover up the incident," Xinhua said, without elaborating.

Infant mortality has declined rapidly in recent years in China due to factors such as better nutrition and improved hygiene.