Four children aged between 5 and 11 were found dead in earthworks at a construction site in Yuanyang county, Henan province, on Saturday.

Seven people, including the manager of the residential building project, are in custody and being questioned, the county government said on Sunday.

The children were all from the county's Wenzhuang village. A preliminary investigation indicated they suffocated after being buried, it said, adding it was unclear how they ended up in the mound.

A preliminary investigation indicated they suffocated after being buried, it said, adding it was unclear how they ended up in the mound

The bodies of the four children were uncovered 1 meter beneath the earthworks, ThePaper.cn, a news portal, reported on Sunday, adding that the construction site had been accused of failing to comply with laws.

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The father of two of the dead children, surnamed Liu, said they were from three different families.

Liu said he discovered his two sons were missing around 5 pm on Saturday, and then received news that the bodies of the children had been dug up at the construction site.

The county government said the developer had not gone through necessary housing construction procedures, and related information was not available at the county's housing bureau.

Feng Xianying, a lawyer with the Yingke Law Firm in Beijing, said the government should strengthen legislative guarantees of juvenile safety.

Due to the novel coronavirus pandemic, children had to study at home, and it was very important to guarantee their safety while they did so, Feng said.

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"Both the schools and the students' families should work together to raise children's safety awareness," she said. "The parents should spend more time accompanying their kids, and it's better that they make a schedule of kids' daily activities."

Family education should highlight safety and psychological education, Feng said, and parents should communicate more with their children and teach them the risks of water, electricity and outdoor activities.

Contact the writers at palden_nyima@chinadaily.com.cn