SINGAPORE (Reuters) -Singapore said on Friday that it was responding to cyberattacks on its critical infrastructure by an espionage group alleged by security experts to be linked to China.

"UNC3886 poses a serious threat to us, and has the potential to undermine our national security," Coordinating Minister for National Security K. Shanmugam said in a speech. "It is going after high value strategic threat targets, vital infrastructure that delivers essential services." 

He did not give details of the attacks, citing security risks, nor of any consequences.

Google-owned cybersecurity firm Mandiant has described UNC3886 as a "China-nexus espionage group" that has attacked defense, technology and telecommunications organizations in the U.S. and Asia.

Beijing routinely denies any allegations of cyberespionage, and says it opposes all forms of cyberattacks and is in fact a victim of such threats. The Chinese embassy did not immediately respond to a request for comment sent after office hours. 

Singapore's critical infrastructure sectors include energy, water, banking, finance, healthcare, transport, government, communication, media, as well as security and emergency services, according to the country's cyber agency.

Reuters earlier this week reported that the Taiwanese semiconductor industry and investment analysts had been targeted by Chinese-linked hackers as part of a string of cyber espionage campaigns.