Rome, Sep 5 (IANS/CMC): Italy’s criminal doping investigation into former 100-metre world record-holder Asafa Powell, Jamaica teammate Sherone Simpson and their trainer has been delayed.

Prosecutor Andrea Gondolo is claiming that his office has been unable to contact the athletes, reports CMC.

Gondolo wants to ask the athletes whether they want to observe the testing of substances sequestered during a police raid in July, on their training base in northern Italy.

"The problem has been finding an address to deliver the notification to see if they want to observe the tests because some of the tests cannot be repeated," Gondolo said Wednesday.

"But I think we should be able to move forward within a month."

The athletes can observe the testing themselves or designate a lawyer to do so and have 20 days to respond once contacted.

Powell, Simpson and Christopher Xuereb were formally placed under criminal investigation for violating Italy's doping laws following a July hotel raid in Lignano Sabbiadoro, where the Jamaicans have been training for years.

The raid came after it was announced that Powell and Simpson had tested positive for the banned stimulant oxilofrine at the Jamaican championships in June.

The athletes blamed Xuereb, their newly hired trainer, and said that new supplements he provided caused the positive tests.

Xuereb responded by saying that he didn't give the sprinters performance-enhancing drugs and suggested he was being made a scapegoat.