Morkel, who took a break from his Indian Premier League (IPL) duties with Chennai Super Kings to attend the funeral here on Saturday, could not be reached for comment.
But Piet Byleveld, now in private practice after a distinguished career as the top detective in the South African Police services, confirmed to the Afrikaans daily Beeld that Morkel had asked him in his private capacity to assist in the investigation.
"If people ask me to assist, I will always do so," Byleveld said.
Former provincial player Vorster was killed and a bag containing a huge amount of money was stolen from his vehicle in broad daylight at a filling station alongside a busy highway last Tuesday.
Amid speculation that it was a planned hit, a close friend of Vorster claimed that the bag contained diamonds, but his wife said that Vorster was on his way to buy some generators for their farm. PTI FH SSC