WMCTV: Police say 4- and 5-year-old siblings have been found dead in the trunk of the family car outside their Springdale, Arkansas home.

The children were reported missing at 4:35 p.m. Monday, and police found the 5-year-old boy and 4-year-old girl in the trunk about a half hour later. Police said Tuesday they would interview neighbors and family members as they try to find out what happened.

Names of the children have not been released. Police have not commented on the cause of death.

Springdale police said the children's mother had last seen them at 3:50 p.m. Authorities searched the house and the surrounding area for 35 minutes before finding the children in the closed trunk.

Medical personnel declared the children dead at the scene.

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