Military officials say an elite soldier has been killed in southern Afghanistan by an explosive device.

The blast is said to have happened late Wednesday or early Thursday.

The Danish army says members of Denmark's Ranger and Frogmen units were on a joint patrol with Afghan police when the soldier was killed.

The soldier was airlifted by helicopter to a field hospital but his life couldn't be saved. Next of kin have been notified.

Denmark has about 750 troops in Afghanistan, mostly based in the volatile Helmand province.

Denmark is due to start withdrawing its combat units this year and gradually shift its role to training Afghan forces.