The man surnamed Zeng left his village in the eastern province of Zhejiang in 2005 after killing his wife's uncle following a rent dispute over 500 yuan ($76), the Zhejiang Daily reported Friday.
Zeng, then aged 33, pretended to be mute and managed to find a job on a construction site in another province. He changed his name, got married and became a father.
But local police eventually became suspicious at Zeng's lack of identity papers. They ordered a blood test and discovered last October that his DNA closely matched that of the parents of the murderer wanted for 12 years.
"By not speaking, I was not going to say anything stupid," Zeng told police in writing. He faces a possible death sentence if convicted of murder.