Washington (CNN) Families crossing illegally at the US-Mexico border in December reached a record high for the fourth month in a row, according to Customs and Border Protection data obtained by CNN.

This comes as the Trump administration has been claiming a humanitarian crisis on the southern border, with President Donald Trump giving an address to the nation Tuesday night to convince the country and Congress that a physical border barrier is needed to deal with the situation.

In December, US Border Patrol arrested 27,518 family members, up nearly 240% from last December, which had 8,120 arrests. Arrests on the border are used by the government as a measure of illegal crossings. There has been a steady upswing in family arrests since August, when 12,760 family members were apprehended.

CBP Commissioner Kevin McAlleenan told ABC News late last month that the department needs a barrier to help push illegal drug traffic into areas that can be better controlled, but also needs "money to provide a better process, a different approach for families and children crossing." In December, 65% of CBP crossings were families and children, he told ABC News' "This Week."

"We don't want them in Border Patrol stations, we want them in a better scenario for these vulnerable populations that we're seeing," he added.

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