Not only is Texas blocking federal border agents’ access to a public park along the Rio Grande in Eagle Pass, but the state is also preventing the agents from using federal equipment and from conducting “operationally necessary” activities in the area, the U.S. Department of Homeland Security alleges in a letter to Texas Attorney General Ken Paxton.

In the letter, sent over the weekend, Homeland Security general counsel Jonathan Meyer said the state must grant U.S. Customs and Border Protection full access to the city-owned park by close of business Wednesday or risk unspecified sanctions from the Justice Department.

“Texas’s actions are clearly unconstitutional and are actively disrupting the federal government’s operations,” Meyer said in his letter. “We demand that Texas cease and desist its efforts to block Border Patrol’s access in and around the Shelby Park area and remove all barriers to access in the Shelby Park area.”

The state’s seizure of the park last week as part of Gov. Greg Abbott’s Operation Lone Star has prompted a multifront pushback by the federal government and has been cited as a factor in the recent drowning deaths of a woman and two children in the Rio Grande because rescue efforts could not be carried out.

Meyer said less publicized actions by the state have also interfered with federal border operations.

More: Migrant mother, two children drown near Eagle Pass; Rep. Henry Cuellar blames Texas policy

“(S)ome of the barriers placed by Texas and the armed soldiers deployed by Texas are on federal land,” he wrote. “Specifically, Texas National Guard is blocking entrances through federally owned and maintained border barriers with armed soldiers.

“While Texas has claimed that it has re-opened the use of Shelby Park to the public, it continues to prevent Border Patrol from entering, and from using the area under the adjacent port of entry where Border Patrol has certain property stored for use when migrants are apprehended.”

In addition to Meyer’s cease and desist letter, Homeland Security has asked the U.S. Supreme Court  to force the state of Texas to allow federal border officials to operate in the park. In a rebuttal to the high court filed Monday, Paxton’s office said Homeland Security is misstating the state’s actions in Shelby Park.

The court filing said federal border agents have access to the park’s boat ramps and that Operation Lone Star personnel “have consistently sought to collaborate with federal border-patrol agencies” in the effort to combat unlawful immigration from Mexico.

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Abbott, meanwhile, stepped up his criticism of President Joe Biden’s immigration policies and made no mention of state-federal cooperation when he posted his reaction to Meyer’s letter on X, formerly Twitter.

“Biden is doing everything possible to eliminate strategies that actually prevent illegal immigrants from entering our country,” the governor wrote. “Texas will continue to use every tool possible to block illegal immigration.”

In recent weeks, the attorney general’s filing said, U.S. border agents have largely ceded immigration enforcement operations at the park to the state.

“When Border Patrol ceased largescale operations at the Park, a Border Patrol officer told state personnel that they would not be back unless the National Guard asked,” Paxton’s office said in the court document.

Without addressing that claim, Meyer said in his letter that the law gives federal border agents wide latitude when it comes to controlling unauthorized immigration, including entering private land without a warrant within 25 miles of the international border.

Border agents sought the OK from state officials to enter the park when several people attempting to cross were in distress on Jan. 10, Meyer wrote.

“Texas refused. Later, a rescue team from Mexico was able to rescue two individuals from the group, both with signs of hypothermia,” he said in the letter. “Three individuals drowned. Texas has demonstrated that even in the most exigent circumstances, it will not allow Border Patrol access to the border to conduct law enforcement and emergency response activities.”

The Homeland Security court filing seeking to regain access to Shelby Park is part of a wider action before the Supreme Court that seeks to overturn a ruling by the 5th U.S. Circuit Court of Appeals ordering border agents not to cut state-installed concertina wire along stretches of the Rio Grande shoreline.

The high court has not indicated when it might rule on the matter.

This article originally appeared on Austin American-Statesman: Federal-state battle over Eagle Pass city park on Rio Grande escalates