Since the wall plans were announced, environmental advocates, federal officials and Tohono O’odham officials have raised concerns about the project, such as the destruction of saguaros, the use of water from the aquifer under Organ Pipe, and the impact the wall could have on migrating animals.

The National Park Service warned in a report last July that construction of the wall on Organ Pipe could destroy artifacts belonging to the Tohono O’odham, as well as remnants of 19th century settlements in the area.

Organ Pipe is adjacent to the Tohono O'odham Reservation and part of the Tohono O'odham's ancestral lands.

The blasting on Monument Hill drew a swift rebuke from U.S. Rep. Raúl Grijalva, a Democrat whose district includes Organ Pipe.

DHS is “bulldozing through numerous sacred sites of the Tohono O’odham Nation — including Monument Hill,” Grijalva said in a prepared statement.

Tohono O’odham elders told Grijalva during a recent tour of the area that bodies were buried on Monument Hill after Apache raids, according to notes from the tour provided by Grijalva’s staff.

“DHS has consistently failed in its legal obligation to consult with the tribes, and this is only the latest example,” Grijalva said.