BEIJING (AP) — Top American officials said Thursday they challenged their counterparts in China to rein in alleged cybersecurity infringements as a new allegation emerged of a brazen attempt by Chinese hackers to break into U.S. government personnel files.

U.S. Secretary of State John Kerry said the two powers had a frank exchange on the issue during this week’s “Strategic and Economic Dialogue” in Beijing. However, Kerry said he and Treasury Secretary Jack Lew only were notified of the latest accusation of wrongdoing after the gathering’s conclusion.