Two people are dead and another injured after a two-vehicle crash in the state's South on Sunday evening.

The crash occurred near the intersection of South Arm Road and Dorans Road in Lauderdale about 6pm when two vehicles were involved in a head-on collision.

A man and a woman travelling together were killed in the crash, while the male occupant of the other vehicle was transported to hospital.  

Police were investigating the cause of the crash on Sunday night.

Acting Sergeant Jon Remess said road conditions were wet and slippery at the time of the crash, but could not confirm whether the conditions were contributing factors. 

Traffic between South Arm and Lauderdale was blocked off for more than two hours until police reopened one lane about 8.15pm.

It is expected to be some time until the scene was completely cleared.

Acting Sergeant Remess said traffic control was made difficult due to the road being the sole thoroughfare to South Arm.

“It was in a position on a causeway which exacerbated the traffic congestion because people couldn’t get out towards South Arm,” Acting Sergeant Remess said. 

“It was in a very tricky position which as a result caused the congestion.”

Ambulance Tasmania and Tasmania Fire Service vehicles also attended the scene. 

The crash brings Tasmania’s road toll to seven for 2017. ​

EARLIER

The road to South Arm is likely to be blocked off for several hours while emergency services attend a serious two-vehicle crash in Lauderdale.

Injuries have not been reported at this stage.

Tasmania Police reported the crash, which occurred near Dorans Road, just before 6pm.

Police have advised motorists to avoid the area, with the road impassable from either direction until the scene is cleared.