2013, when he says he realized that he was sowing chaos, murdering the poor and innocent, and serving evil.

He's been under witness protection and remains in hiding. He has an outstanding case against his former boss and the Philippines' current president, Rodrigo Duterte, who is under investigation by the country's Human Rights Commission.

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Warrant pending

The government also has an arrest warrant out for him -- for not showing up in court on charges of possession of illegal firearms -- and has also charged him with a kidnapping in 2002.

Even though he's claimed to have killed dozens of people, they wouldn't dare charge him with murder, he says, as that would bean admission of wrongdoing on the part of the Duterte administration.

After decades in the employ of the Davao City government -- as an assassin, he says -- Matobato has now turned against his former paymaster.

In testimony to the Philippines Senate in September, Matobato said he was part of the Davao Death Squad (DDS), which he alleges was run on the orders of Duterte.

"Our work was to kill criminals like drug pushers, rapists, snatchers," he testified at the time. "Those were the people we killed every day."

CNN has not independently confirmed Matobato's allegations.

Duterte's office denied the claims made by Matobato under oath, and said the President was "unfazed" by the Senate investigation.

Secrecy at all costs

We are met on the road by his handlers some distance away from the compound,