Officials in the northern Mexico border state of Coahuila say an empty assembly plant used to house about 1,600 Central American migrants during the past two weeks has closed.

Jose Borrego, a state spokesman, confirmed the closure of the Piedras Negras shelter Tuesday, a day earlier than scheduled. He said additional information would be made available later.

The shelter's population had been steadily falling since last week as migrants who had obtained humanitarian visas were given bus rides to other cities where they could have a better chance of finding work.

The migrants arrived at the border hoping to request asylum in the United States, but Mexican authorities corralled them in the shelter and only about a dozen were allowed to request asylum each day.