U.S. Border Patrol agents arrested around 2,000 more immigrants crossing the border between official points of entry in May compared to April, up from 38,234 to about 40,400, according U.S. Customs and Border Protection statistics.

Overall, including immigrants who turned themselves in at ports of entry, more than 50,000 immigrants tried to enter the U.S. by land over the U.S.-Mexico border last month — the third straight month to surpass 50,000.

Unaccompanied children crossing illegally increased from 4,302 in April to 6,405 in May, while the number of parents traveling with children decreased slightly.