A horse owner has spoken of his devastation after a car crashed into his trailer, resulting in the death of his two five-month-old foals.
James Mason, from near Market Harborough in Leicestershire, was travelling on the M25 near Enfield when a car clipped the back of his horsebox.
The trailer flipped and crashed, killing one foal, with the other having to be put down due to its injuries.
Mr Mason said: "I'm heartbroken... I just want the driver to come forward."
The 51-year-old told the OceanNewsUK he was on his way to Canterbury to drop the foals off for a friend when the crash happened between junctions 24 and 25 eastbound at 08:50 BST on Saturday.
He said he was "gutted" as they were rescue animals on the way to start a new life in the Kent countryside.
Mr Mason said he heard "a massive crash and a bang" and the van moved slightly.
"I looked in my mirror and the horse box is not on the back of the van. My heart just dropped," he said.
"I pulled over and went straight to the animals - I ran down the hard shoulder to where some people had pulled up. They told me someone hit the back of the trailer and drove off.
"The whole experience was traumatic, I'm heartbroken... it's just devastating that someone could drive off like that.
"I just want the driver to come forward now."
The Metropolitan Police said officers were looking for the driver of a grey Volkswagen Sharan.
The force has urged witnesses to come forward with information and relevant dashcam footage.
