The U.S. government on Wednesday warned that a hacking group widely known as cloudhopper, which Western cybersecurity firms have linked to the Chinese government, has launched attacks on technology service providers in a campaign to steal data from their clients.

The Department of Homeland issued a technical alert for cloudhopper, which it said was engaged in cyber espionage and theft of intellectual property, after experts with two prominent U.S. cybersecurity companies warned earlier this week that Chinese hacking activity has surged amid the escalating trade war between Washington and Beijing.