A pedestrian hit by a lorry in Holderness Road, east Hull, is believed to have died.
The road is closed in both directions from Mount Pleasant to Southcoates Lane after the accident near Barnsley Street.
It happened at around 3.20pm and emergency services are at the scene.
Police say the pedestrian is a man in his 60s or 70s.
The Mail understands he has died of his injuries.
Some distressed staff from nearby shops who witnessed the accident were later sent home early.
Holderness Road is expected to reopen at around 7pm, police said.
Updated 5.40pm. More to follow
Motorists are experiencing severe delays on east Hull routes.
Roads in and out of the city centre are gridlocked.
Bus firm EYMS said the crash has affected all services heading to east Hull, Bilton, Hornsea and Withernsea.
Buses are being diverted out of the city centre down Mount Pleasant, New Bridge Road and Southcoates Lane.
Heading into the city buses are going via Summergangs Road, James Reckitt Avenue and Mount Pleasant.
Bus stops on Holderness Road between the Summergangs/Southcoates area and Mount Pleasant are not being served. Commuters are advised to wait for a bus on one of the diversion roads.
EYMS chairman Peter Shipp said: "New Bridge Road isn't exactly designed with buses in mind and is very narrow.
"A lot of traffic is being diverted around the area, so it is very crowded.
"We are trying our best to get people home and safe, but unfortunately our services are delayed.
"We want to apologies to all our customers affected by the delays."
Updated 5.40pm. More to follow
