While the motive for Thursdays shooting by a masked man at a cinema complex in western Germany remains unclear, police has repeatedly warned that the country could be a target by the Islamic State terror group.

Germany absorbed more than 1 million refugees last year, and there have been concerns about the possibility of IS cells in the country.

In Thursdays incident, wearing a disguise and armed with a gun and cartridge belt, the man fired several shots into the air before apparently taking several cinema-goers who were gathered in the multiplex hostage, before being shot dead.

Cops said none of the people taken hostage were harmed, AFP reported.

Dozens of screaming bystanders fled the complex with reports of between 25 and 50 injured, though the exact number of casualties has not yet been confirmed.

Police later said those injured were affected by teargas and were being treated by local medics.