By Dustin Volz
WASHINGTON (Reuters) - U.S. Department of Homeland Security employees in the Washington area were unable to access some agency computer networks on Tuesday, according to two sources familiar with the matter.
It was not immediately clear how widespread the issue was or how significantly it affected daily functions at DHS, a large government agency whose responsibilities include immigration services, border security and cyber defense.
Employees began experiencing problems logging into networks at 5 a.m. ET on Tuesday due to the expiration of the personal identify verification cards used by federal workers and contractors to access certain information systems, one source said. At least four DHS buildings were affected, the source said, including locations used by U.S. Citizenship and Immigration Services.
DHS did not immediately respond to requests for comment.
Government agencies redoubled efforts to implement the use of "smart" cards for network log-ins following the 2015 discovery of a massive hack at the Office of Personnel Management that compromised nearly 22 million background check records.
President Donald Trump vowed to make cyber security a priority during his administration. At a White House event last month he said he would "hold my Cabinet secretaries and agency heads accountable, totally accountable, for the cyber security of their organizations."
(Reporting by Dustin Volz; Editing by Jonathan Oatis)