Trump: 'We will close the border permanently if need be'

President Trump threatened to permanently close the U.S. border with Mexico on Monday, saying he'll take the drastic action if members of a swelling migrant caravan are not deported back to their Central American homelands.

U.S. Border Patrol fired tear gas canisters and rubber bullets at a group of migrants on Sunday, including families with young children, as hundreds tried to storm the border. 

San Diego Sector Border Control chief patrol agent Rodney Scott said Monday morning on CNN that when the migrants approached border fences, they 'immediately started throwing rocks and debris at our agents, taunting our agents.'

'And once our agents were assaulted and the numbers started growing – you know we had two or three agents at a time facing hundreds of people at a time – they deployed tear gas to protect themselves and protect the border.'