Trump says up to 15,000 troops will be sent to US-Mexico border to counter 'migrant caravan'

Civil liberties group accused president of politicising military ahead of midterms

Donald Trump has said the US could send up to 15,000 troops to the border with Mexico, as the president hardens his stance against a caravan of migrants fleeing poverty and violence in Central America.

The number is significantly higher than US defence officials have disclosed. Initially, the Pentagon said it was deploying more than 5,200 troops to the border, but on Wednesday it said more than 7,000 would support the department of homeland security along the border.

If 15,000 troops are drawn into the effort, it would mean there would be more US troops on the border with Mexico than there are in Afghanistan, which has become America's longest conflict.

"As far as the caravan is concerned, our military is out ... We'll go up to anywhere between 10 and 15,000 military personnel, on top of Border Patrol, ICE and everybody else at the border," Mr Trump told reporters at the White House.

He did not say how many of those 15,000 would be National Guard personnel. There are already 2,100 National Guard forces at the border, sent after a previous request by Mr Trump in April. They are authorised to go up to 4,000.

Several groups, including the American Civil Liberties Union, have accused Mr Trump of politicizing the military ahead of next week's congressional elections with his plans to use active military personnel to buttress border patrol efforts.

Mr Trump has sought to use immigration as an issue to motivate Republican voters ahead of the 6 November elections, where Republicans will seek to maintain control of both congressional chambers.

As a presidential candidate before the US election in 2016, Mr Trump promised to harden immigration laws and build a wall along the southern border with Mexico, but implementation of his signature campaign promise has been slow.

A caravan of Central American migrants estimated to number at least 3,500 people left Honduras in mid-October and is now in southern Mexico on its way to the US border.

Before Mr Trump's comments, US defence secretary Jim Mattis on Wednesday rejected criticism that deploying thousands of troops to the border with Mexico was a political stunt.

"The support that we provide to the secretary for homeland security is practical support based on the request from the commissioner of customs and border police, so we don't do stunts in this department," Mr Mattis said after a meeting with his South Korean counterpart at the Pentagon.

Republican lawmakers and other Trump supporters have applauded the deployment. But critics argue Mr Trump has manufactured a crisis to drive Republican voters to the polls.

"The move to send 5,200 active duty troops to the southern border is a craven political stunt that sets a bad precedent and is arguably an abuse of power," said Kelly Magsamen, a former senior Pentagon official who is currently with the Center for American Progress, a left-leaning think tank.

Mr Trump's decision to call in the military appears to be a departure from past practice. In recent years, such operations have been carried out by National Guard forces, largely part-time military members often called upon to respond to domestic emergencies.

A US official told Reuters that as of Wednesday the Pentagon had identified more than 7,000 active-duty troops, which included about 2,000 on standby, that could be deployed to the border with Mexico if needed.

Many basic questions remained unanswered days after the Pentagon announcement, including the scope of the mission as well as the Pentagon's assessment of any threat posed by arriving migrants.

Additional reporting by Reuters