Police have begun a murder probe after two children were found dead inside an 18th century wooden chest.
Anna and Mikhail Presnov, 10 and 7, are believed to have climbed into the family heirloom and suffocated after a latch closed preventing them from opening the heavy lid.
However, law enforcement in Ukraine have not ruled out foul play.
The pair were home alone in the village of Mykilske when their parents went to dig potatoes as seasonal workers some 29 kilometres away.
Their parents, Svetlana, 35, and Stanislav, 41, say they spoke to the children at 10am but an hour later, they did not answer the phone.
The mum and dad did not raise the alarm with neighbours but instead waited for their bus home in the late afternoon, and began a search for the missing girl and boy.
“I took a bicycle, Svetlana went on foot along the nearby streets looking for them, but there were no signs of them,” said the dad, an ex-miner.
The pair had been seen playing outside in the morning but a police sniffer dog directed officers back into the family home.
It was the police who found the bodies inside the antique wooden chest, which had been passed from generation to generation in the family, originally as a dowry.
"During a search of the house, the children were found in an old chest with no signs of life," a statement from National Police in Ukraine said.
"The forensic service is currently working at the scene. The circumstances are being established.
"Police are considering all versions of the deaths of the brother and sister."
A murder case has been opened.
Brother and sister buried next to each other
The children's dad said police told him it was most likely an accident.
"They got inside, the chest closed and they suffocated. There's a bracket through which to put a padlock.
"The latch might close in a way they could not open it from the inside.
"But the point is that they could have lifted the lid so that there was a gap for air…"
The children have since been buried next to each other.
"The children loved their parents and the parents loved the children," Svetlana Zhigailo, the children’s headteacher, said at the funeral.
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