WASHINGTON — Democratic critics of President Donald Trump are accusing him of “militarizing” the southern U.S. border with his latest decision to deploy about 800 active-duty troops there to assist with security efforts.

“The president’s (decision) is fundamentally wrong and a political act at a time when leadership is needed,” House Armed Services Committee ranking member Adam Smith, D-Wash., said in a statement late Thursday evening. “We should not be militarizing the border, and President Trump has offered no clear idea of what our forces are going to do there.”

Earlier on Thursday, Pentagon officials confirmed that the force of 800 troops will help bolster the effort of 2,100 National Guard servicemembers already working in southwest states, in support of border security operations.

Trump has said the additional personnel are needed to deal with a caravan of migrants traveling from South America towards the United States. He has also accused Democrats and their backers of encouraging or supporting the caravan, to undermine national security.

Before the deployment news, House Minority Leader Nancy Pelosi, D-Calif., and Senate Minority Leader Chuck Schumer, D-N.Y., blasted Trump’s border security talk as little more than a political stunt on the eve of the midterm elections, saying he is “desperate to change the subject from health care to immigration.”

Smith, who is in line to take over as the Democrat’s top voice on defense issues if his party gains control of the House in November, said that administration officials have shown “no evidence that it was helpful or effective when he sent the National Guard to the border in April.”

“The caravan of people that the President is focused on are coming to seek asylum, and they have a lawful right to do so,” he said. “There is absolutely no reason to further politicize and militarize this humanitarian crisis.”

Pentagon officials have said they will work closely with Department of Homeland Security leaders to detail what the troops’ roles and limitations will be. Officials could not say whether the troops will be armed.

A memo on guardsmen’s roles written this spring them from interacting with migrants or taking on a law enforcement role.

Reporters Tara Copp and Steve Losey contributed to this report.