McALLEN, Texas (AP) — The drowning deaths of three migrants have brought new urgency to an extraordinary showdown between the Biden administration and Texas Republican Gov. Greg Abbott, who has seized a city park in a major corridor for illegal crossings and denied entry to Border Patrol agents.

The Department of Justice filed a new request late Monday with the Supreme Court to grant federal agents access to a portion of the border along the Rio Grande that is occupied by the Texas National Guard and the Texas Military Department. The request followed the drownings of a young Mexican mother and her two children who tried to enter the U.S. through the river near Shelby Park at Eagle Pass, Texas.

The state fenced off Shelby Park last week and has been denying the public and federal agents access to the city-owned land as part of Abbott’s aggressive actions to stop illegal crossings. The drownings occurred hours after President Joe Biden’s administration first asked the Supreme Court to intervene.

Abbott posted on social media Monday that he is using “every tool possible to stop illegal immigration.”

The Department of Homeland Security and the Texas Military Department have provided different timelines about the drownings since they were made public Saturday by a South Texas congressman.

According to the Justice Department’s filing Monday, the deaths occurred at 8 p.m. Friday, an hour before U.S. federal agents were notified by Mexican counterparts. Border Patrol agents were also made aware of two other migrants in the same area who were in distress, the filing said.

U.S. agents approached the closed gate at the park’s entrance and informed the Texas National Guard of the situation, the filing said. They were told Texas was denying them access to the 50-acre (20-hectare) park “even in emergency situations.”

The filing was made in a lawsuit that the Biden administration filed over razor wire fencing installed by Texas. An appellate court issued an order in November barring federal agents from cutting or moving Texas’ razor wire except in emergencies.

“Even when there is an ongoing emergency of the type that the court of appeals expressly excluded from the injunction, Texas stands in the way of Border Patrol patrolling the border, identifying and reaching any migrants in distress, securing those migrants, and even accessing any wire that it may need to cut or move to fulfill its responsibilities,” the Justice Department wrote in the most recent filing.

The U.S. government has said Border Patrol agents used the park to monitor the river and to launch boats into it. Texas has countered that the Border Patrol withdrew most of its agents and equipment from Eagle Pass after the appellate court issued its injunction.

The Justice Department asked the Supreme Court to throw out that entire order.