WASHINGTON (AP) — The Veterans Affairs Department said Thursday its undersecretary responsible for benefits is leaving.

The agency has been besieged by complaints about its backlog in claims, which have escalated, in part, because of Iraq and Afghanistan veterans seeking assistance.

Daniel L. Cooper, a retired Navy vice admiral, departs April 1. A VA spokesman said Cooper was leaving for personal reasons.

Cooper was credited by the VA with helping the agency strengthen its outreach efforts and improve its communication on the Internet during his six years in the position.