IBM is believed to be among the US tech giants attacked by hackers on behalf of the Chinese government.

According to multiple news outlets, the attack was part of a decade-long campaign known as Cloudhopper. The hackers allegedly targeted managed service providers (MSP) used by companies like IBM to manage their IT operations remotely, in a bid to gain access to their client networks, and then steal customer information.

The MSPs have not been named, but could cover a range of roles – from networking to hardware such as servers and storage.

In total, it is believed that around 45 US tech companies and government agencies were compromised.

On Thursday, multiple sources reported that the Department of Justice has charged two Chinese nationals with being part of the campaign.

It comes at time of heightened tension between the US and China. Apart from an escalating trade war between the two countries, the US recently coordinated with Canada the arrest of the CFO of Huawei, one of China’s biggest companies.

“As evidenced by this investigation, the threats we face have never been more severe, or more pervasive, or more potentially damaging to our national security, and no country poses a broader, more severe long-term threat to our nation’s economy and cyber infrastructure than China,” FBI Director Christopher Wray was quoted as saying by The Verge.

IBM didn’t comment on the specific details of the attack, but did provide a statement.

“IBM has been aware of the reported attacks and already has taken extensive counter-measures worldwide as part of our continuous efforts to protect the company and our clients against constantly evolving threats,” IBM said. “We take responsible stewardship of client data very seriously, and have no evidence that sensitive IBM or client data has been compromised by this threat.”