Emergency services are at the scene of a road traffic collision in Co Down on Sunday morning.
The Belfast Road, Ballynahinch, has been closed for several hours following the serious two-vehicle crash.
It is understood the road will remain close for some time this morning.
Diversions are in place at the junction of the Saintfield Road and at the Creevytenant Road.
Motorists are advised to avoid the area and seek an alternative route for their journey.
A PSNI spokesperson told Belfast Live: "Police in Downpatrick are appealing for information following a serious two vehicle road traffic collision on the Belfast Road, Ballynahinch, in the early hours of Sunday 27th February.
"The collision, involving a black Toyota Landcruiser and a silver Volkwagen Golf, occurred at around 1.15am. A man was taken for treatment following the collision and remains in hospital at this time. The Belfast Road is closed at present whilst officers remain at the scene conducting a number of enquiries.
"Officers would ask anyone who witnessed the collision or anyone who was travelling on the Belfast Road at the time of the collision and who may have captured dash-cam footage which could assist them with their enquiries, to contact police at Downpatrick on 101, quoting reference number 140 27/02/22."
