Citing the U.S. defense spending slowdown and other economic pressures, Northrop Grumman’s Electronic Systems sector announced it would be laying off 140 of its 20,000 employees effective May 31.

Baltimore-based Northrop Grumman Electronic Systems builds defense and aerospace electronics, including sensors for a variety of satellites. Its Azusa, Calif., plant, for example, provides the infrared cameras used on the Pentagon’s missile-warning satellites.

In an email response to a query, Northrop Grumman spokesman Jack Martin said most of those receiving layoff notices work in engineering and manufacturing. About 70 affected employees are in Maryland — the post layoff work force in that state will total about 8,000 — with the remainder in Virginia, Connecticut and elsewhere, the email said.

“All affected individuals will receive all separation and other benefits for which they are entitled and the company will also provide outplacement assistance to help those who will be seeking other employment, including at other Northrop Grumman facilities,” he said. “These work force reductions are due to a near-term reduction in our business volume that is directly related to the current slow-down in defense spending as well as increasing international economic pressures.”