The U.S. has said it is “confident” about sharing intelligence with Japan, following fears that this could be curtailed in the wake of a report that Chinese hackers had infiltrated Tokyo’s most sensitive defense networks, as Beijing looks to disrupt U.S. and allied operations in the event of a conflict over Taiwan.

The Pentagon on Tuesday looked to soften the blow of the explosive report by The Washington Post, which said that the “shockingly bad” hacking had been uncovered by the U.S. in the fall of 2020 and had given China “deep, persistent access” to information about “plans, capabilities, assessments of military shortcomings.”

The report, citing unnamed current and former U.S. and Japanese officials, said the hackers had continued to access the classified networks for about another year through 2021, despite appeals from American officials asking Tokyo to seal the gaps in their systems. While Tokyo eventually took steps to strengthen its networks, U.S. officials hinted that the systems remain insufficiently secure from Beijing’s prying eyes.