KARLSRUHE, West Germany (AP) _ West German authorities arrested a Polish intelligence agent earlier this month on spying charges, but a news leak kept them from arresting another Pole, the Federal Prosecutor's office said Tuesday.

Federal Prosecutor Kurt Rebmann said the second Pole was a ''leading'' spy in West Germany.

Rebmann confirmed a recent newspaper report that 1st Lt. Jerzy Kaczmarek, 33, was taken into custody March 15 in connection with espionage carried out in the north German city of Bremen and other areas.

The prosecutor identified Kaczmarek as an officer of the Polish intelligence service.

Rebmann said news of the impending arrest of the second Pole was leaked to the newspaper Die Welt.

The prosecutor's office declined to say when charges would be filed against Kaczmarek, who is being held in investigative custody. He gave no further details.