A drawing being mocked as the world's worst police sketch has helped Bolivian police track down a murder suspect, Sky News reported.

The picture was released in the South American country following the savage slaying of taxi driver Rafael Vargas, Sky News reported.

It was reportedly drawn by a female witness after what police think could be a drug-related killing or a crime of passion.

Bloggers compared the e-fit's egg-shaped face, crudely-drawn features and straw-like hair to the Wizard of Oz's scarecrow, Ninemsn website said, according to Sky News.

Vargas' burnt body was found in March with 11 stab wounds.

A man had reportedly threatened the victim at his home months before the murder.

Vargas was allegedly accused of having an affair with the aggressor's wife and warned: "You're going to die and you don't know how," Sky News reported.

Click here for more from Sky News.