The U.S. government has confirmed that hackers with links to China breached multiple U.S. telecommunication service providers to access the wiretap systems used by law enforcement to surveil Americans.

An FBI investigation into reported hacks at AT&T and Verizon reveals 'a broad and significant cyber espionage campaign,' the agency says.

WASHINGTON (Reuters) -China-linked hackers have intercepted surveillance data intended for American law enforcement agencies after breaking in to an unspecified number of telecom companies, U.S. authorities said on Wednesday.