An intelligence expert briefing senators on Russian election interference bluntly urged lawmakers to 'follow the trail of dead Russians' to uncover what really happened in the presidential election.

Former FBI special agent Clinton Watts testified at the first public Senate Intelligence hearing probing Russian election interference. He is a fellow at George Washington University's Center for Cyber and Homeland Security.

Panel member Sen. Ron Wyden of Oregon asked Watts to 'tell us about corruption in Russia so as to help us follow the money in our investigation,' as the committee probed decades of Russia's efforts to impact elections around the world.

Watts answered, then adding a more gruesome area of inquiry: ‘The other part that I think we should be looking at is: Follow the trail of dead Russians.'

'There’s been more dead Russians in the past three months that are tied to this investigation who have assets in banks all over the world,' he continued.

Clint Watts, right, a Senior Fellow at the Foreign Policy Research Institute Program on National Security, testifies before the Senate Intelligence Committee at its first hearing into Russian 'active measures.' He urged senators to 'follow the trail of dead Russians'

Some, but not all of the deaths he referenced were in Moscow.

'They are dropping dead even in western countries. We’ve seen arrests I believe in Spain in different computer security companies that are based in Russia which provide services to the United States. These are all huge openings to understand how they are funded by the Russian government,' he said.

Watts didn't mention any specific incidents, but the deaths, some explained, some that were under investigation, have trickled out in media accounts.

Among the most prominent is the death of former KGB general named Oleg Erovinkin, who was found dead in the back seat of his car in Moscow. An initial report is that he was found dead shot twice in the head on Dec. 26.

He was a close aide to Igor Sechin, the chairman of Rosneft who is mentioned in the 'dirty dossier' that former British Intelligence agent Christopher Steele compiled on Donald Trump.

Watts in his testimony acknowledged he was not the foremost Russia expert, but came to the issue through his focus on ISIS and cybersecurity.

He didn't elaborate on his statement that the deaths were 'tied' to the investigation.

Clint Watts, a Senior Fellow at the Foreign Policy Research Institute Program on National Security said he 'came to active measures mostly because active measures came after me' after he got hacked

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An article in the Telegraph referenced speculation that his death was tied to Sechin, a confidant of Vladimir Putin's, appearance in the dossier.

Watts' mention of Spain was a reference to the arrest of a Russian computer programmer wanted in the U.S. for alleged hacking. Spanish authorities cooperating with the FBI arrested the 32-year-old at the Barcelona airport January 13, Reuters reported.

Russia's ambassador to Turkey, Andrei Karlov, was assassinated while speaking at an art gallery in Ankara in an act famously captured on video December 19.

On the same day, another diplomat, Peter Polshikov, was shot dead in his Moscow apartment.

Russia's ambassador to the UN, Vitaly Churkin, died in New York a day before his 65th birthday.

Oleg Erovinkin (left), the former head of the KGB, was found dead in the back of his car on December 26. He was suspected of helping former British spy Christopher Steele (right) compile a dossier that contained unconfirmed allegations against President Donald Trump

In late January, Moscow's ambassador to India, Alexander Kadakin (above), died after suffering from 'a brief illness.' He was 67 years old

On January 9, Andrei Malanin, the Russian consul in Athens, was found dead in his apartment (seen above from the outside). Greek police said they found no evidence of a break-in

NYPD sources said he died of a heart attack, and President Vladimir Putin was 'deeply upset' by the news, having greatly valued Churkin's professionalism and diplomatic talent, according to a Kremlin statement quoted by the Russian news agency TASS.

Russia's ambassador to India, Alexander Kadakin, died in January at 67 after suffering a 'brief illness.'

Officials said he suffered a heart attack, The Hindu reported.

Another Russian diplomat, Sergie Krivov, a 63-year-old security officer, was found dead on the morning of Election Day – November 8 – at the Russian Consulate in New York.

New York's medical examiner now said Krivov died of internal bleeding related to a tumor.

On December 19, Russia's ambassador to Turkey, Andrei Karlov (left), was assassinated by a gun-wielding Turkish police officer (right) at a photo exhibit in Ankara

On January 9, Andrei Malanin, the Russian consul in Athens, was found dead in his apartment.

Putin has denied interfering in the U.S. elections, and he did it by using a famous quote from a U.S. president.

'Watch my lips, no,' Putin said.

The Russian strongman made the claim Thursday when asked point-blank whether Russia had interfered and whether any evidence to the contrary would get found.

He invoked former President Reagan, although the 'Read my lips' quote was actually used by his successor, George H.W. Bush, speaking at a CNBC event on Arctic issues.