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Three days after Gov. Greg Abbott tweeted a legally dubious invocation of the “invasion clause” of the U.S. and Texas constitutions over the high number of migrant encounters at the Texas-Mexico border, his border mission is set to include armored personnel carriers designed to carry troops into battle alongside tanks, according to a planning document obtained by Army Times and The Texas Tribune.

The order issued Thursday by Texas Military Department officials to the headquarters overseeing Operation Lone Star reveals that the National Guard will soon deploy 10 of the M113 armored personnel carrier vehicles to the border.

According to the order, around 50 soldiers will be trained to operate the vehicles, and state officials will identify 10 positions to station them along the border.

The Texas Military Department said in a written statement that in addition to the 10 armored vehicles, the Texas National Guard is increasing “aircraft flights and security efforts” on the border.

“These actions are part of a larger strategy to use every available tool to fight back against the record-breaking level of illegal immigration,” the department said. “The Texas National Guard is taking unprecedented measures to safeguard our border and to repel and turn-back immigrants trying…