More than 800 unaccompanied migrant children were apprehended in a single day this week, as the numbers of migrants coming to the southern border continue to surge.

Health and Human Services announced that 834 unaccompanied children and teenagers were apprehended on Thursday, significantly higher than the 30-day average of 512.

The numbers reflect a continuing surge at the southern border. More than 188,000 migrants were encountered in June, including increases in UACs and migrant family units. The Associated Press reported this week that that number is expected to rise to more than 210,000 for July.

Republicans have blamed the Biden administration’s rollback of key Trump-era policies for the surge, while the Biden administration has instead emphasized “root causes” like violence, poverty and climate change in Central America.

This is a breaking news story; check back for updates.