By JAN M. OLSEN
COPENHAGEN, Denmark (AP) — NATO believes that damage to two natural gas pipelines in the Baltic Sea is the result of sabotage. The military alliance says it will retaliate for any attacks on the critical infrastructure of its 30 member countries. The warning came as a fourth leak was found on the Nord Stream pipelines, off southern Sweden. NATO said Thursday that the damage to the pipelines running between Russia and Germany “is of deep concern.” It said the leaks seem to be “the result of deliberate, reckless, and irresponsible acts of sabotage.” But NATO refrained from saying who it thinks is responsible, even as some members and experts point the finger at Russia.