Children stopped at border likely hit record-high in July

The number of children traveling alone who were picked up at the Mexican border by U.S. immigration authorities likely hit an all-time high in July, and the number of people who came in families likely reached its second-highest total on record, a U.S. official said Monday, citing preliminary government figures.

The sharp increases from June were striking because crossings usually slow during stifling — and sometimes fatal — summer heat.

U.S. authorities likely picked up more than 19,000 unaccompanied children in July, exceeding the previous high of 18,877 in March,...