A MASKED robber held up a post office at knifepoint this morning (Friday).The balaclava-clad man burst into the Martins shop in High View, Hatfield, just before 5.45am, threatening a worker with the weapon.

A MASKED robber held up a post office at knifepoint this morning (Friday).

The balaclava-clad man burst into the Martins shop in High View, Hatfield, just before 5.45am, threatening a worker with the weapon.

When the assistant called for help, he fled the scene, empty-handed.

He drove off in a dark green car, possibly a Ford Mondeo. Police said two other people were inside the vehicle.

The robber is described as white, 5ft 10in, slim. He was wearing a white tracksuit and white gloves.

Call Pc Cheryl Johnson with information on 0845 33 00 222.