SAN DIEGO (CNS) - The latest in more than three dozen bomb hoaxes at Naval Base San Diego or nearby shipyards occurred today, interrupting work and forcing federal law enforcement agents off their regular investigations.

Two threats were made at Pier 7 at the base today -- one written on a ship bulkhead, according to the Navy, which has reported 37 bomb threats since November.

Previous threats have been written inside portable toilets, a ship's stairway, berthing bulkheads and plumbing pipe -- among other places. A few threats were called in.

"While these threats have all been hoaxes, each one is approached with the urgency and seriousness a threat to human life warrants,'' said Gunnar Newquist, special agent in charge of the Southwest Field Office, Naval Criminal Investigative Service.

"The deliberate attempts to interrupt maintenance and operations on our nation's warships are a serious matter and will ultimately cost the U.S. taxpayer hundreds of thousands of dollars,'' Newquist said. "The penalties for

hoax bomb threats, regardless of how vague, are severe and we will prosecute to the fullest extent possible.''

The NCIS is asking for the public's assistance to identify those responsible, and together with shipyards BAE Systems and NASSCO, is offering a $20,000 reward for information that leads to an arrest.

Anyone with such information can call the NCIS at (619) 556-1364. An anonymous text can be sent to 274637 -- type ``NCIS" at the beginning of the text, then type and send the message, including as much information as

possible.