Texas Gov. Rick Perry gave one thousand National Guard troops a rousing sendoff as they begin their duty along the Rio Grande, but the governor declined to say how long the mission will last or when it will end, Newsradio 1200 WOAI reports.

  Perry dispatched the Guard last month at the height of the influx of immigrant children from Central America.  That surge has generally abated, but Perry told Guardsmen at Camp Swift near Bastrop that the mission of Operation Strong Safety' is to deter criminal activity and protect Texans.

  "Texas put out the call and you have answered," Perry said.  "Your mission is clear, to be a visible presence to deter criminal activity, and contribute additional eyes and ears to assist law enforcement and Border Patrol agents along the border."

  Sheriffs along the Rio Grande say Perry would have had more impact on crime by using the $12 million a month the Guard deployment will cost to boost the operations of local sheriff's departments.  They say the Guard will not be able to make arrests.

  Many Rio Grande Valley residents are wary of additional militarization of the border.  Last fall, a DPS 'surge' along the border resulted in annoying roadblocks that citizens had to deal with on their way to work and to the store.

  In addition, the surge of Central American immigrant children, which the Guard deployment was meant to deal with, has generally ended.

  Perry, a former U.S. Air Force transport pilot, returned a snappy salute from Adj. Gen. John Nichols when he arrived to address the soldiers and airmen.

  He said when the call went out for 1,000 volunteers, more than 2200 volunteered for the assignment.