ANCHORAGE, Alaska (Reuters) - Two members of the U.S. Coast Guard were found shot to death at an air base on Kodiak Island in Alaska on Thursday, and the installation was placed on a security alert, the Coast Guard said.The two were found dead at a communications facility at the Coast Guard Base Support Unit Kodiak, and authorities were looking for a potential suspect who might be at large, according to a Coast Guard statement.Because circumstances of the shooting were not immediately clear, the Coast Guard said the base, located about 250 miles southwest of Anchorage, was placed on lockdown as a precaution, as were nearby schools in the area."Since we don't have all the details, we strongly advise that all Kodiak residents remain vigilant and to report any suspicious activity to local law enforcement officials," Coast Guard Captain Jesse Moore, the commanding officer of the base, said in the statement.