Federal state and local law enforcement arrested over 600 undocumented immigrants during a week-long targeted enforcement operation in the Houston area, U.S. Immigration and Customs Enforcement officials said.

Federal officials have been mostly mum about the specifics of their actions across the Houston region in recent weeks. In Monday’s announcement, they said federal investigators had executed 71 warrants and arrested more than 543 people accused of crimes and seven gang members as part of the operation. They did not identify the people arrested.

Nearly 650 undocumented immigrants, including 543 criminals and seven gang members, were arrested during a week-long enforcement operation in the Houston area.