One man and three horses have died following a road collision.
The incident happened on the A14 near Sproughton in Suffolk at 10.20pm on Christmas Eve.
Police were called following reports that up to six horses were loose on the road followed by a collision involving four vehicles.
A Suffolk Police spokeswoman said: "The man, aged 23 years and from Cambridgeshire, has since sadly died today.
"A section of the A14 westbound carriageway between Copdock and Sproughton was closed in order to recover the vehicles and horses, three of which died as a result of the collision."
The A14 has now re-opened.
A 26-year-old Ipswich man arrested on suspicion of causing danger to road users, has been bailed pending further inquiries.
Witnesses are asked to call PC Ali Cotton at the Serious Collision Investigation Team at Suffolk Police on 101.