A Texas trooper in an email sent to his superiors on July 3 and obtained by NBC News on Tuesday details a number of different incidents in which he describes how he and his partner were ordered to abandon migrants as well as deny them water in what has been one of the hottest global summers on record. 

Immigrant and civil rights groups are now calling on local and federal officials to investigate the allegations made by the trooper for the Department of Public Safety. 

An internal investigation into the allegations is underway, according to the Texas Department of Safety while Democrats in the Texas Capitol also plan to investigate they said. The Department of Homeland Security has denounced the allegations in a statement but did not mention if the agency was planning to investigate. 

The trooper in the email said the incidents took place from June 24 to July 1 in Eagle Pass, Texas, while working on Gov. Greg Abbott’s border security initiative, known as Operation Lone Star.

He has authorized over $4 billion in spending on Operation Lone Star, which also includes his busing of thousands of migrants to Democratic hubs and arresting migrants on trespassing charges.

The specifics of the email were first reported by the Houston Chronicle on Monday. 

According to the email, the trooper alerted a supervisor that they’d come across a group of 120 migrants on June 25, including young children and mothers nursing babies before being told to “push the people back into the water to go to Mexico.”

The name of the trooper and who the email was sent to is still unknown as of publication. 

The trooper responded and warned of “the very real potential of exhausted people drowning,” the email reads but the trooper and his partner were ultimately ordered to leave. 

“I believe we have stepped over a line into the inhumane,” the trooper said in his email.

However, in a joint statement Tuesday, Gov. Abbott denounced the idea of such orders being given to border troopers. 

“No orders have been given under this mission that would compromise the lives of those attempting to cross the border illegally,” the statement read. 

Lt. Chris Olivarez, a spokesperson with the Texas Department of Public Safety, said on Wednesday that “our troopers have not in any way forcefully pushed any migrant — let alone a child — back into the river.” 

He added that the department has no instruction or policy ordering troopers to push migrants back into the water. The state has put up miles of razor wire as well as created a wall of buoys along the Rio Grande, the email also mentions. 

Domingo Garcia, president of the League of United Latin American Citizens (LULAC), the nation’s oldest Latino civil rights organization, condemned the alleged prevention acts "and any other barriers that jeopardize the safety of women and children seeking asylum." 

Juan Jose Martinez-Guevara, an advocacy manager for United We Dream, the U.S.’ largest immigrant youth-led organization, said the allegations "are the realization of years of dangerous, dehumanizing, anti-immigrant rhetoric."

In one account from June 30, the trooper said he viewed a 4-year-old girl attempting to cross through razor wire be “pressed back” by Texas National Guard soldiers in accordance with orders. The girl later fainted from the extreme heat, according to the email. 

The trooper's email also cites an order from his superiors to not provide water to those attempting to cross the river and in the surrounding areas. Officials at the Texas Department of Safety have denied such an order. 

The trooper called on his superiors to "provide a safe means of travel on solid land to proper collection points," according to the email. He said the directive to not give people water, even under extreme heat conditions, "needs to be immediately reversed as well."

White House press secretary Karine Jean-Pierre on Tuesday told reporters that the trooper’s allegations, if found to be true, are “abhorrent” and “dangerous.”

“If this is true, it is just completely, completely wrong,” Jean-Pierre said.