Plans to build a liquid natural gas facility at the Port of Brownsville are being challenged by a Native American tribe.

After years of anticipation and challenges to NextDecade LNG facility, construction on the site began this month.

Aerial views show a lot of vegetation in the area is already gone as the company is clearing a road and square pads along the way from its entrance on Highway 48 to the Brownsville Ship Channel.

RELATED: Construction for Port of Brownsville LNG export site underway

“This is contaminating the area, it's contaminating the water," Juan Mancias — tribal chair of the Carrizo Comedrudo tribe said, adding that land in and around the construction site is their native homeland.

“They won't let us access the land to go and see and make sure that these are not sacred sites,” Mancias said. “And we know for a fact that they are. They're depriving us of our religious freedom to even honor our dead there."

Mancias submitted a cease and desist letter to NextDecade and the Port Of Brownsville to stop disturbing burial sites and archaeological resources.

Construction is happening within the ecologically sensitive lomas, low-lying mounds of soil held together by vegetation. Mancias says they’re also significant to his tribe.

NextDecade is proposing to raise billions of dollars to create a natural gas export facility similar to what's already operating in Corpus Christi. The facility supercools natural gas into liquid form to make it compact and able to transport on a cargo ship, bringing jobs with it.

The Port of Brownsville and NextDecade have not responded to the cease and desist letter or to Channel 5 News regarding what’s going on at the site.

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