Richmond Hill will remain closed until midday at the latest following a collision.
Police say it involved two vehicles, and other vehicles previously reported had just stopped at the scene.
Accident investigation work is now taking place at the junction of New Castletown Road and Mount Murray.
The public is asked to use St Marks or Old Castletown Road to avoid Richmond Hill.
Investigators say fatal Manx ship sinking 'avoidable'
Family's appeal to bring brain-injured dad home
Island animal charity appeals for help after relentless bad weather
Further appeal for witnesses following incident in Ramsey
Speed restrictions planned for the coast road next week
Hundreds paid by cheque after MiCard scheme scrapped
No drone zone on Tynwald Day
Last orders at the bar as ‘Spoons puts counter up for sale