Washington ? Secretary of Defense Robert Gates has declared a moment of silence for U.S. military forces worldwide as a show of respect for the Fort Hood victims.

The moment of silence is planned for 2:34 p.m. EST Friday — exactly 24 hours after the shooting in Texas. All U.S. forces worldwide are being asked to participate in the show of respect.

A spokesman says Gates has no immediate plans to travel to Fort Hood.

Army Chief of Staff George Casey and Army Secretary John McHugh arrived at the base Friday.