The International Criminal Court has raised concern over the killing of a man who has been described by other officials as a witness in the trial of Kenya's Deputy President William Ruto.

The ICC said late Tuesday the victim, Meshack Yebei, was not listed as a prosecution witness but the court had offered Yebei a safe residency in a new location. Yebei was abducted from his home town in western Kenya on Dec. 28. His body was found five days later.

Ken Wafula, a human rights activist who has been in contact with Yebei's family, says Yebei had been dropped as a prosecution witness.

Ruto and radio journalist Joshua Sang are on trial for crimes against humanity for the 2007-08 post-election violence where more than 1,000 people died.