A man armed with an axe has gone on the run after fleeing from the scene of a four-vehicle crash.
He is thought to have been driving a van which was involved in the smash in Sheepscar, Leeds, at 17:30 GMT on Saturday.
A search has been launched for the man, who is described as white, in his 30s or 40s, with a black beard and a flat cap.
He was last seen running into woods in the Headingley area of the city.
Leeds Beckett students said they were on "lockdown" and had been told not to leave their accommodation.
'Do not approach'
The university confirmed that staff and students at its Headingley campus had been "asked to remain inside for several hours".
The search prompted dozens of comments on social media.
Police keeping us in our accommodation because there’s a lunatic booting about with an axe, I love Leeds— Thomas Cullen (@_Thomascullen) February 10, 2018
Hi #Headingley West Yorkshire Police are pursuing a man with an axe last seen near St Chads - please be sensible & safe. If you see anything contact the Police & Cllrs.— Neil Walshaw (@CllrWalshaw) February 10, 2018
It is believed the man used the axe to remove a locked bicycle close to St Chad's Rise before going into the woods.
Supt Lisa Atkins said: "We would urge anyone who sees this male not to approach him and to contact police on 999 so we can locate him and detain him."