An historic Texas chapel stands in the way of President Trump’s proposed border wall, and some Senate Democrats are rallying to protect it.

In a Thursday letter to Department of Homeland Security Secretary Kirstjen Nielsen, first obtained by the Fort Worth Star-Telegram, Sens. Chuck Schumer (D-NY), Dick Durbin (D-IL), Tom Udall (D-NM), and Martin Heinrich (D-NM) interrogate the administration’s plan to use eminent domain to seize land from border-town religious groups, despite the move possibly violating religious freedom.

“Eminent domain should not be involved in violation of any religious organization’s First Amendment right of free exercise of religion, Fifth Amendment right to just compensation for any public taking of private property, or the Religious Freedom Restoration act,” the senators wrote.

At the center of their argument is the Roman Catholic Diocese of Brownsville, which is currently battling the Trump administration over its its request to survey or seize its land for border-wall construction. The diocese has called the wall “fundamentally inconsistent with Catholic values” and warned that, in particular, Trump’s plans could limit access to or totally destroy the La Lomita chapel, a 153-year-old church widely considered the “heart of the community” in the border city of Mission, Texas.

That historic missionary church, located near a horseshoe bend in the Rio Grande separating the United States from Mexico, stands about 800 feet from the border.

“The federal government must exercise extreme caution when seizing private property, especially with respect to sacred sites like Lo Lomita Chapel,” the senators’ letter said. “The Trump Administration’s lawsuit against the Diocese raises important questions on the exercise of eminent domain to build a border wall and the impact it will have on religious organizations and American taxpayers.”

The Diocese of Brownsville—which has a hearing on Feb. 6 on their challenge against the government’s attempt to survey their land for possible construction—said on Friday that they are “pleased to see that members of Congress are concerned about the federal government's overreaching use of the power of eminent domain.”

“As the Diocese stated in its briefing to the court, and as the senators reiterated in their letter to Secretary Nielsen, the proposed border wall is fundamentally inconsistent with Catholic values,” said Mary McCord, senior litigator for the Georgetown’s Institute for Constitutional Advocacy and Protection, who is representing the diocese. “The Diocese looks forward to seeing the Secretary's response to the congressional letter."

Bishop Daniel Flores, who has led the diocese since 2009, told The Daily Beast on Friday that the congressional letter gives him hope that their efforts are “being heard all the way in Washington”—all over the roughly 65 acres of land in dispute.

“I am so happy that leaders in Washington have heard about our fight,” Flores said. “We are not backing down because this fight is more about the government taking away our land. It is about La Lomita and what the chapel means to our community, our parishioners, and our history.”

As previously reported by The Daily Beast, the Catholic chapel, built in 1899, is known as “the mother church” among the community and their southern neighbors, many of whom often cross the border to pray at the chapel. In a border town of 84,000 where an estimated 85 percent of the population is Catholic (the highest concentration in the United States, according to the church), the chapel plays an integral role in Mission’s history.

“Everybody sees this as our mother church and it’s forever sacred in our memory,” said Father Roy Snipes, a 73-year-old clergyman who leads a nearby Catholic church. “It’s the heart of our community. It’s like a second home to me.”

The senators pointed out in their letter that the Trump administration has not provided any information about how many landowners will lose property along the southern border, or when the government expects to complete its seizure process.

“Given that 67 percent of the land along our southwest border belongs to entities other than the federal government, we are troubled that President Trump has not provided any estimates regarding the impact of using eminent domain to build a border wall,” the letter said.

To gain a better picture of what the government plans to seize, the senators gave Nielsen until the end of the month to release information about how many religious organizations and citizens should expect to be affected by Trump’s border-wall plans.

A DHS spokesperson confirmed to The Daily Beast that the agency and Secretary Nielsen received the Thursday night letter, but declined to comment further.