COPENHAGEN, Denmark (AP) — Swedish police say they have arrested two adults on suspicion of murder after two children fell from “a great height” and one of them died.

Those arrested are a man and a woman, police said. The children who were reportedly were siblings and both under the age of 10, were rushed to the hospital. One of them died there; the other child has life-threatening injuries, police said.

The Expressen tabloid said the children’s father had stabbed the children before throwing them out of the window of their apartment in western Stockholm late Sunday.

A passerby found the children and alerted police.