A cyberattack on the Washington Post compromised email accounts of several journalists and was potentially the work of a foreign government, company officials told some affected staffers in recent days, according to people familiar with the situation.

Staffers were told the intrusions compromised journalists’ Microsoft accounts and could have granted the intruder access to work emails they sent and received, some of the people said. The reporters targeted include those on the national security and economic policy teams, including some who write about China, the people said.