D.C. Public Schools says student information from 55 schools, including families' addresses, could have been exposed due to a data breach, according to school officials. DCPS officials told News4 Thursday that the hack involved a website that was storing student data from 55 schools, mainly elementary schools, with after-school programs run by DCPS, as well as data from students in summer programs. Tony Monell, who works for the cybersecurity firm Black Kite, told News4 that people should use multifactor authentication whenever possible. Monell said that although he is not part of the DCPS investigation, he’s noticed a hacker group on the dark web claiming responsibility for the breach. "We understand that data security incidents are concerning and sincerely regret that this occurred," the DCPS letter said.