a necessary caution. He's in danger of being killed himself these days, as a key witness to -- and actor in -- what he says was a series of unspeakable crimes from 1988 to 2013.

During that time he says he was part of the DDS, an allegedly state-sanctioned group of murderers who, alongside him, he says, killed as many as 1,400 people in the southern city under then-Mayor Duterte.

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At first, he thought he was doing something just: ridding his town of bad people. But over the course of his career as a hit man he came to realize that he wasn't on the side of justice. In 2010,he says, he was ordered to kidnap and kill bodyguards and associates of one of Duterte's political rivals. Of the four bodies they dumped in the sea, two resurfaced.

It was one of the incidents that chipped away at an already dented conscience, leading to his recent claim that he was a killer for Duterte.

Another time, he recalls, three young women suspected of dealing shabu -- the local name for methamphetamine -- were bound, beaten and raped by DDS members, then killed.

Marked for death

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His former colleagues -- who numbered 300 at the height of the group's existence -- would kill him if they find him,