Judge halts Navy use of sonar in war games

LOS ANGELES — A federal judge issued a temporary restraining order Monday barring the Navy from using a type of sonar, allegedly harmful to marine mammals, during a Pacific warfare exercise scheduled to begin this week.

The order comes three days after the Navy obtained a six-month national defense exemption from the Defense Department allowing it to use "mid-frequency active sonar."

Environmental groups had sued to stop the sonar use during the exercises off Hawaii. The sonar portion of the war games was set to start Thursday.