Police are appealing for information about a hit-and-run crash which left two children with serious injuries.
A blue Volkswagen Golf lost control in Harwood Street, Blackburn, Lancashire and hit a red Volkswagen Golf travelling in the opposite direction at about 3pm on Friday.
The occupants of the blue Golf got out of the vehicle before a white Vauxhall Astra van arrived at the scene a short time later.
One of the occupants then got into the boot of the van before it drove off towards Eanam, said police.
One of the passengers in the red Golf, a 12-year-old girl, suffered a fractured skull and internal injuries, while a second passenger, a two-year old girl, suffered head and neck injuries.
Both are receiving treatment at Royal Manchester Children's Hospital.
The driver of the red Golf, a 39-year-old woman, suffered minor leg injuries.
Sgt Adam Dawson, from Lancashire's road policing unit said: "This collision has left two children with serious injuries and an investigation is under way to trace the occupants of the blue Volkswagen Golf and the van.
"If anyone witnessed the collision or has any information that could assist with our inquiries I would urge them to get in touch. I would also appeal to the occupants of the other two vehicles involved in the collision to make contact with us."
Anyone with information should contact Lancashire Police on 101 quoting 766 of April 14, or alternatively the independent charity Crimestoppers can be contacted anonymously on 0800 555 111 or online at crimestoppers-uk.org.