Donald Bruce Campbell was last seen at Sandy Bay on October 20, but it is believed that he went walking in the Claremont area on October 23 or 24, setting out from the Claremont Village Shopping Centre.

His car has been found at the shopping centre.

Mr Campbell is described as five foot, eight inches (about 172 centimetres), with a thin build and short grey hair.

He is a former marathon runner and is known for running and walking in bushland areas.

Anyone with any information should contact Glenorchy Police on (03) 6173 2777.