San Diego

General Dynamics said Friday it has suspended the general manager and three other employees at its Electronics Division in response to a San Diego Union story detailing how one of its reporters breached security at the company’s plants earlier this week.

An internal investigation is under way to determine the circumstances of the security violation, General Dynamics said in a prepared statement. The four employees, including general manager Melville R. Barlow, will remain under suspension until the inquiry is completed.

The San Diego-based Electronics Division makes defense-related products, including test and training equipment for military aircraft. General Dynamics’ Convair division makes the Tomahawk cruise missile. All General Dynamics plants are off-limits to personnel who do not have security clearance.

The security breach occurred at one of the company’s Kearny Mesa plants.

“This comes at a time when all of our operations are under heightened security restrictions as a result of the potential for terrorism,” General Dynamics President James R. Mellor said in the statement explaining the suspensions.