Local police have detained eight suspects, including the manager of a residential building project and an excavator driver, after four children were found dead at a construction site in Henan province on Saturday, Xinhua News Agency reported on Monday.

The tragedy occurred in earthworks at a construction site in the Henan's Yuanyang county on Saturday.

Xinxiang city and Yuanyang authorities immediately set up a joint team to conduct a full-scale investigation after the accident.

A preliminary investigation indicates that the four children may have entered the site through a gap in the fence, and they might have been buried by loose earth that fell on them as they played on the site.

All the children were from the county's Wenzhuang village. Their bodies were uncovered 1 meter beneath the earthworks, news portal ThePaper.cn reported on Sunday, adding that the construction site had been accused of failing to comply with laws in construction.

According to the official statement, the children were uncovered one by one between 5:30 pm and 10:40 pm on Saturday.

An autopsy was conducted on a victim that was retrieved from the earth on Saturday night, China Youth Daily reported. The results of the autopsy have not yet been released.

Villagers erected a mourning hall on Sunday morning for the victims, and an expression of "deep remorse" was written at the mourning site.

Further investigation is underway, and the local county government has declared it will provide updates on the case on its website.