US-bound migrant caravan from Honduras a 'national emergency': Trump to military

President Donald Trump said in a tweet on Monday that he had alerted the U.S. military and federal border authorities that a U.S.-bound migrant caravan from Honduras was a national emergency, but gave no other details.

"Sadly, it looks like Mexico's Police and Military are unable to stop the Caravan heading to the Southern Border of the United States," Trump wrote in a post on Twitter, adding: "I have alerted Border Patrol and Military that this is a National Emergy."