The U.S. Department of Homeland Security said Tuesday the number of people apprehended trying to cross into the country from Mexico fell by 36 percent between December and January, reaching its lowest level in a year.
There were 23,767 total apprehensions in January compared to more than 37,000 in December. The department said the figures are an indication of the overall number of attempts to get into the country illegally.
In the beginning of January, immigration authorities arrested 121 people in the first of new raids targeting families who had illegally entered the United States. Homeland Security Secretary Jeh Johnson did not link the arrests with the drop in border apprehensions, but did renew his defense of the policy announced last November.
He said the decline is "encouraging," but that the government cannot reduce its border security operations.
"Our borders are not open to illegal immigration," Johnson said. "If someone was apprehended at the border, has been ordered deported by an immigration court, has no pending appeal, and does not qualify for asylum or other relief from removal under our laws, he or she must be sent home."
The American Civil Liberties Union criticized the January deportations, calling them a "scare tactic" to deter families from fleeing Central America to the United States.
The Mexican border accounts for an overwhelming majority of the country's illegal border crossings.
Homeland Security data indicate January used to be a time when apprehensions at the southwestern U.S. border spiked. Between 2000 and 2009, the number of apprehensions nearly doubled — and in some cases tripled — between December and January.
That trend began declining in 2010, and since 2014 the apprehensions in January have been lower than in the prior month.
The data also show a huge decline on a year-by-year basis during the past decade, falling from about 1.7 million apprehensions in 2005 to 330,000 in 2015.