The top government watchdog overseeing the Pentagon will review how U.S. troops have been used on the southern border, saying he has received “several requests” to do so.

Glenn Fine, acting Defense Department inspector general, said his office will examine what the service members are doing, what training they received and whether they have complied with laws, Pentagon policy and operating guidelines they received.

“We intend to conduct this important evaluation as expeditiously as possible,” Fine said in a statement to The Washington Post.

The decision comes after 34 members of the House requested a review in September, according to a letter that Fine sent Rep. Raúl M. Grijalva (D-Ariz.) on Tuesday.

“We have carefully reviewed your request — as well as considered other factors — and have decided to initiate an evaluation of U.S. military operations along the southern border,” Fine wrote.

Nineteen senators issued a similar request to Fine last spring, Sen. Richard Blumenthal (D.-Conn.) said in a statement released Tuesday.

Fine said in a memo to Defense Secretary Mark T. Esper and other senior defense officials on Tuesday that he is requesting several different military commands to provide a main point of contact for the project.

Senior officers who received the memo include Gen. Mark A. Milley, chairman of the Joint Chiefs; Gen. Terrence O’Shaughnessy, the commander of Northern Command; Adm. Craig Faller, the commander of Southern Command; Gen. Joseph Lengyel, chief of the National Guard Bureau; and Lt. Gen. Charles D. Luckey, the commander of Army Reserve Command.

Lt. Col. Christian Mitchell, a Pentagon spokesman, said that the service has received the memo and is aware of Fine’s requests.

The assessment of training will examine in part how service members have been trained for potential contacts with civilians. It also will scrutinize interaction and coordination between U.S. troops and the Department of Homeland Security, which oversees border security, Fine said in the memo.

The Trump administration first deployed active-duty service members to augment homeland security personnel and National Guardsmen last year, with President Trump floating the idea in April and following through late in October, just ahead of Election Day.

The move, carried out as a caravan of migrants traveled north through Mexico from Central America, was decried by critics as an unnecessary step that politicized the military and sapped attention from other missions. While Presidents Barack Obama and George W. Bush sent National Guardsmen to the southern border, they stayed away from deploying active-duty forces following a 1997 case in which Marines searching for drug smugglers killed a teen herding goats near the U.S.-Mexico border.

At the height of the deployment in late 2018, about 5,900 active-duty troops were along the southern border. Their missions have included spreading thousands of miles of concertina wire and operating surveillance equipment to watch for smugglers coming across the border.

The number of active-duty troops has dropped to about 2,400 in recent months, supplemented by about 2,600 National Guardsmen. Trump authorized Defense Department support for the border through 2020 of up to 5,500 service members at a time.

Grijalva said Tuesday that he believes the military should have no role in enforcing domestic law and that Trump’s deployment of troops to the southern border erodes laws and norms that keep domestic law enforcement and the military separate.

“Congress and the American people deserve to know why the Trump Administration is politicizing our military and whether the Trump Administration is forcing them to violate federal law under his orders,” Grijalva said in a written statement. “I welcome this investigation and firmly believe that our servicemembers and border communities should not be pawns in Trump’s political games.”

Blumenthal said in his statement that he welcomed the review, and believes “accountability is long overdue.” He called the deployments to the border politically motivated.

“Over the last two years, the Trump Administration has manipulated our military for partisan gain in a dangerous disservice to our men and women in uniform, and a threat to military readiness and our national security," Blumenthal said.