Chinese efforts to hack American figures are far more widespread than previously reported, ABC News has learned.

Sources told ABC News that U.S. law enforcement and intelligence agencies are concerned that the Chinese government-led spying operation has been in place for more than a year – and possibly longer – before being recently discovered.

The Chinese appear to have succeeded in collecting large volumes of data in a massive covert campaign targeting the cell phones and mobile devices of business leaders and other prominent Americans from both political parties, sources say close to the investigation.

Evidence is mounting that in some cases the Chinese operation was able to exploit or access the cell phones of Verizon, AT users.&T and Lumen were communicating.

Authorities are trying to determine whether the Chinese were able to listen to the conversations and watch the text messages in real time as they were happening, or whether they captured the material for later review.

Sources said U.S. officials are only beginning to understand the scale of Chinese operations, but what they have discovered so far is deeply concerning and represents a massive invasion of privacy on a disturbing scale.

MORE | Top Trump lawyer’s cellphone compromised by Chinese hackers, sources say

The targets included not only former President Donald Trump and Senator JD Vance, but also people working in a number of government agencies.

The FBI routinely contacts victims, sources said.

Salt Typhoon, the name given to an advanced and persistent threat actor led by the Chinese government, is believed to be behind this operation.

Intelligence officials suspect the Salt Typhoon hackers of exploiting the routers as a gateway to cellphones and mobile devices, and there are concerns that Chinese intrusion capabilities have made significant advances.

In a statement last month, Verizon representatives said: “We are aware that a highly sophisticated state actor may have targeted multiple U.S. telecommunications providers to gather intelligence. In collaboration with federal law enforcement, our industry peers, and third-party cyber experts, we have been and are working to confirm, assess, and remediate any potential impacts. Verizon is committed to assisting law enforcement in this investigation.

Representatives for AT&T and Lumen declined to comment.

According to sources, the FBI determined that Blanche’s communications with family and friends were compromised, and investigators are still trying to determine whether communications with more sensitive contacts were affected.

Sources told ABC News that Blanche is potentially considering becoming Trump’s next White House legal advisor or taking on a high-level law enforcement-related role under a new Trump administration.

The massive Chinese hacking operation made national headlines two weeks ago, when the FBI issued a statement saying it was investigating recently identified “malicious activities” by government “affiliated actors” Chinese who targeted commercial telecommunications infrastructure.

The statement said the FBI and the Department of Homeland Security’s Cybersecurity and Infrastructure Security Agency notified victims of the operation. This apparently included private companies and individuals, who then increased their security measures and replaced the compromised cell phones, according to sources.

ABC News previously reported that Trump and his running mate, Sen. JD Vance, learned last month that they and others associated with the campaign were among the victims whose cellphones were targeted. Democrats were also targeted, we learned on ABC News.

The FBI believes the hackers were unable to access encrypted apps on the targeted phones, but the investigation is still ongoing to confirm this and identify other victims, according to sources.

Earlier this week, the Wall Street Journal reported that hackers linked to Chinese intelligence services had compromised phone lines used by politicians and senior U.S. government national security and policy officials, allowing the hackers to “ recover call logs, unencrypted texts and some audio files of potentially thousands of Americans and others with whom they interacted. »

Asked about ABC News’ latest reporting, an FBI spokesperson declined to comment.

Steven Cheung, Trump’s spokesperson, said in a statement: “Make no mistake, foreign adversaries are terrified of President Trump’s strength and determination. President Trump will stand against our enemies and defend the United States against all aggression. He will not let anything stop him or prevent him from fighting for the American people and making America great again. »

Blanche oversaw Trump’s defense during the former president’s weeks-long criminal trial in New York, where a jury convicted Trump in May of 34 counts of criminal fraud stemming from his role in falsifying business records to conceal secret payments to adult film star Stormy Daniels to improve her electoral chances in the 2016 presidential election.

Sentencing is scheduled for later this month, although it is unclear whether that will still happen after Trump is re-elected to the White House on Tuesday.

After Trump’s conviction in May, Blanche told The Associated Press that Trump “knows there’s still a lot of fight left and there’s a lot of opportunity to solve this problem and that’s what we’re going to do.” try to do.”