Updated

South African police say they are hunting “day and night” for suspects after three children were found tied up and stoned to death.

Bafana Kekana, Hosea Richard Kekana and Johana Kekana, ages 9, 10 and 12, respectively, were reported missing Thursday after they didn’t return to a youth care center where they had been living, according to a statement from the South African Police Service. The children participated in a school march Wednesday that called for more teachers.

The children's bodies were found by a resident in Naboomspruit, a town in the northeastern part of South Africa, on Saturday, still in their school uniforms with their hands and feet bound by shoelaces.

The South African Police Service also says bloody stones were found near the bodies and that the girl, Johana, had apparently been raped.

“We will hunt the perpetrators day and night; we will follow all the leads and no stone will be left unturned,” said Lieutenant General Simon Mpembe, the provincial commissioner of the Limpopo Police.