A major crash involving a number of police cars has shut the A1 on Tyneside, leading to long delays.
Images from the scene near Denton, Newcastle, show four marked police vehicles badly damaged, a car on its side, and debris scattered across the northbound carriageway.
One of the police vehicles had its roof torn off.
Crash investigators have been sent to the scene of the pile-up, which happened at around 2.30am on Wednesday.
National Highways said the A1 will be closed between Swalwell in Gateshead and Denton in both directions into Wednesday afternoon.
It said: “A multi-vehicle collision resulting in serious injuries occurred at approximately 0230 this morning (Wednesday 9th April).
“Due to the severity of the collision a full Northumbria Police investigation is under way and they advise that it will be protracted.
“The road is expected to remain closed in both directions into the afternoon of Wednesday 9th April.”
A Northumbria Police spokesman said: “Shortly before 2.30am today (Wednesday) we received a report of a multi-vehicle collision on the A1 northbound near the Derwenthaugh Road junction, Gateshead.
“Emergency services are currently in attendance.
“A section of the road is closed in both directions – there are diversions in place from the Derwenthaugh Road junction northbound, and the A69 roundabout southbound.
“Motorists should use alternative routes where possible.”
