A gunman opened fire at a disco in southern Germany early Sunday, killing one and wounding four before being shot by police, officials said in a statement.

The 34-year-old attacker "was critically injured in a shootout with police officers as he left the disco, and later succumbed to his wounds in hospital," police said in a statement.

"The motives of the man, who probably acted alone, are not known yet," added police.

The man had begun shooting in the nightclub in the southern German city of Constance at around 4.30 am (0230 GMT), fatally wounding one and leaving three other people seriously wounded.

Shortly after he left the disco, he was shot by police. One officer was also injured in the exchange of fire.

Terrified nightclubbers had either fled the building or found a place to hide, said police.

Police said in a statement that special commando forces have been deployed in the city as it was not clear if the suspected had acted alone or had accomplices.

The shooting came just two days after Germany was shaken by a knife attack in the northern port city of Hamburg.

A 26-year-old Palestinian had killed one and injured six in an assault at a supermarket.

He was a known to the police due to psychological problems, and investigators say his motives remain unclear.