A German zoo says it has recaptured one lion but had to kill another after they escaped from their cage overnight.

The Leipzig Zoo said no people were injured in the incident after the juvenile lions somehow escaped from their enclosure.

Zoo officials said one lion was successfully corralled back into its cage and the second was shot with a tranquilliser.

Zoo director Joerg Junhold told the dpa news agency that the tranquilliser failed, however, and the lion had to be shot.

Mr Junhold said: "in this case the safety of people came first."

The two male lions, Majo and Motshegetsi, were born about a year ago in Switzerland's Basel Zoo and had been at the Leipzig Zoo since August.

It was not clear which lion was killed.