An investigation is currently ongoing after a member of the Texas National Guard reportedly shot a man from across the U.S.’s southern border.

Authorities claim that a guardsman on the Texas side of the Rio Grande fired at and struck a man on the Mexican side.

Mexican authorities from the Chihuahua State Attorney General’s Office have not publicly revealed information regarding the alleged victim, aside from saying that the individual is a 22-year-old man currently receiving medical treatment.

The information from the Chihuahua AG disputes earlier reports from Mexican health officials, which said the wounded individual was a 37-year-old man who had already been released.

However, according to El Diario de El Paso, the incident occurred around 9 p.m. on August 26, close to the Bridge of the Americas that connects El Paso and Ciudad Juárez.

Initially, the injured man reportedly said he was a migrant from Veracruz but later changed his story when speaking to media outlets, suggesting instead he was playing an undisclosed sport close to where a group of migrants were attempting to cross the river, El Diario reported.

The Texas Military Department stated, “On the night of 26 August, a National Guard Servicemember assigned to Operation Lone Star discharged a weapon in a border-related incident. … The incident is under investigation.”

“More information will be made available as the investigation progresses,” the military department added. Mexican authorities are conducting an investigation as well.

The incident comes as tensions over the ongoing border crisis have continued to rise.

As reported by The Dallas Express, the federal government has sued Texas over a series of buoys designed to deter unlawful border crossings. Gov. Greg Abbott has promised to take the case all the way to the Supreme Court if necessary.

Some Texas politicians have openly called for the impeachment of Department of Homeland Security Secretary Alejandro Mayorkas for failing to secure the border. The crisis has even led one elected official to change political parties from Democrat to Republican.

However, the Department of Homeland Security maintains, “The Administration’s plan is working as intended.”

Others have criticized Operation Lone Star, suggesting that it has led to inhumane treatment of those attempting to enter the country unlawfully.

Texas Sen. Roland Gutierrez (D-San Antonio) recently sent a letter to U.S. Attorney General Merrick Garland demanding an investigation into security measures implemented by the operation at the border.

“Since he launched Operation Lone Star more than two years ago, Gov. Abbott has taken drastic measures to curb illegal immigration. … What began as a farce has now turned into violent, horrifying injuries and death,” Gutierrez claimed.