An Arizona lawmaker is raising the alarm about the federal government’s U.S.-Mexico border wall construction — which, he said, is literally blowing up the location of sacred Native American burial grounds.

Rep. Raúl Grijalvawrote in a Jan. 7 letterto the Department of Homeland Security that he’d spoken with leaders from the Tohono O’odham Nation tribe who were upset about how the department was moving forward with construction of PresidentDonald Trump’s controversial wall along the Mexican border.

“There has been no consultation with the nation,” Grijalva, 71,told CBS News. “This administration is basically trampling on the tribe’s history — and to put it poignantly, its ancestry.”

“Where they were blasting the other day on Monument Hill [in Oregon Pipe] is the resting place for primarily Apache warriors that had been involved in battle with the O’odham. And then the O’odham people in a respectful way laid them to rest on Monument Hill,” Grijalvasaid in a Sunday videoposted to social media.

Ina statement toThe Washington Postand other outlets, CBP said that what was happening was “controlled blasting.”

“The construction contractor has begun controlled blasting, in preparation for new border wall system construction within the Roosevelt Reservation at Monument Mountain,” a spokesperson said in a statement. (Monument Hill is also called Monument Mountain.)

“The controlled blasting is targeted and will continue intermittently for the rest of the month,” the CBP spokesperson continued.

An “environment monitor” has also been present, the government said, according to thePost. (The CBP did not respond to PEOPLE’s request for comment.)

“Contractors are building the 30-foot-tall steel wall on the side of the hill [Monument Hill] as part of a 43-mile project on Organ Pipe and the adjacent Cabeza Prieta National Wildlife Refuge,”theArizona Daily Starreportedon Saturday.

Although Trump’s border wall cannot be built on the Native American reservation because it is private land, the burial sites are located on public land right next to the reservation, according to CBS News.

Carolyn Van Houten/The Washington Post via Getty

Organ Pipe Cactus National Monument border fence

Grijalva expressed “serious concerns” in his January letter to the DHS and urged the department to “conduct meaningful government-to-government consultation with the Tohono O’odham Nation about the DHS’s planned border wall construction.”

But Grijalva told CBS last week that he hasn’t heard back.

“There’s been stonewalling, no response for any request,” he said.

Grijalva also wrote in his letter to the DHS that the Trump administration has been “irresponsible” in its powers under a post-9/11 legistlation called the REAL ID Act which allows the skirting of environmental laws in the name of national security.

“This administration continues to use its waiver authority at an unprecedented and irresponsible rate: of the 21 times the waiver has been enacted since 2005, 16 of those instances have occurred in the last two and a half years,” Grijalva wrote.

In the widely shared video posted on his Twitter account on Sunday, Grijalva, a Democrat and Trump critic, said the president “blew up a sacred Native American hill on public land to build his racist wall.”

The Mexico border wall is a key promise of the Trump administration dating back to his 2016 campaign.

Construction is proceedingafter legal fightsand a rebuke from Democrats in Congress over funding, which the president circumvented with the use of military money.

“Given that building ‘the wall’ was Trump’s No. 1 campaign pledge, it is no surprise that he has been so obsessed with building it,” Peter Andreas, a border wall historian at Brown University, told PEOPLE in January. “It is still a long way off, so much so that ‘finish the wall’ will undoubtedly be a lead campaign pledge in the next election.”

source: people.com