LONDON (Reuters) - Germany's domestic intelligence service will put the far-right "Reichsbuerger" movement under observation, officials said on Tuesday, just weeks after one of its members shot dead a policeman during a raid at his home.

The move came a week after the spy agency's chief told Reuters that ultra-rightists in Germany are increasingly ready to commit violent acts and are networking with like-minded groups across Europe, and even in the United States.

Members of the Reichsbuerger (Citizens of the Reich) do not recognize modern-day Germany as a legitimate state, and insist the former, far larger "Deutsche Reich" is still alive despite Nazi Germany's defeat in World War Two.

"We agreed this week that the 'Reichsbuerger' will be the object of observation by domestic intelligence in all of Germany with immediate effect," Interior Minister Thomas de Maiziere told the Bundestag (lower house of parliament).

"The danger emanating from this group has significantly increased over the last year," he later added in a statement. "It is time to take a closer look at what they are doing."

The Interior Ministry estimates that the Reichsbuerger have several thousand members.

One of them shot dead a police officer in Bavaria in October as a police team was about to enter his home to seize his hunting and sports guns, which the authorities deemed he was not fit to hold as a member of the group.

Four other police officers were injured in the shooting.

(Reporting by Sabine Siebold; Editing by Paul Carrel)