A bus, part of a Chinese tour group heading to Milford Sound, has crashed at Lowther, on the Athol Five Rivers Highway (SH6) this morning (8 Jul).

Police said emergency services were alerted at 8.26am, with Fire and Emergency NZ crews from Lumsden, Garston, Mossburn and Athol attending.

Hato Hone St John said two operations managers, three ambulances, one PRIME responder, and one first response unit also attended.

12 patients in total were assessed at the scene, with four being transported to Invercargill Hospital, one in a serious condition, two in moderate condition and one in minor condition.

The remaining 8 patients were in minor condition and did not require transportation to hospital, they said.

The south-bound lane remains closed and Police have ask drivers to avoid the area and take alternative routes where possible.

Police said there was reports of black ice in the area and they urged people to drive to the conditions and consider black ice during cold times of the day.