There were 104,344 people encountered in June, down from 144,278 the month before. May saw a record high number of families cross.
The number of families crossing in June wasn’t immediately released Tuesday, but Homeland Security officials say the tally was down across the board.
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The figure includes both apprehensions between ports of entry, and people who were deemed “inadmissible” by Customs officers.
The numbers usually drop during hot summer months, but this year’s tally is 11 per cent lower than last year’s May-to-June decline.
The decline comes amid renewed outcry over conditions at facilities, and a crackdown by Mexico on migrants crossing from Central America.