China alleges that the U.S. National Security Agency launched cyberattacks during the Asian Winter Games in February

BEIJING—Chinese police issued wanted notices for three people they said engaged in cyberattacks against China on behalf of the U.S. National Security Agency, a rare step by Beijing as hostilities between the superpowers escalate.

China’s outing of alleged US National Security Agency hackers marks a major escalation in the ongoing tit-for-tat between Chinese and American intelligence agencies, according to analysts.