WASHINGTON – The Justice Department has put Texas Gov. Greg Abbott on notice that it intends to file suit over a floating barrier wall he erected in the Rio Grande River to keep migrants from crossing the border illegally.

“The State of Texas’s actions violate federal law, raise humanitarian concerns, present serious risks to public safety and the environment, and may interfere with the federal government’s ability to carry out its official duties,” the department wrote in a letter to Abbott on Thursday, according to published reports.

Hearst Newspapers and CNN obtained a copy of the letter.

The threat of legal action comes amid reports of inhumane treatment of migrants along the U.S. border with Mexico. Some migrants attempting to cross the border have reportedly been left bloody from razor-wire barriers installed at Abbott’s instructions. State troopers also reportedly were ordered to deny migrants water in sweltering heat and instructed to push them back into the river.