Umpires Simon Taufel and Aleem Dar and third umpire Brian Jerling reported the offspinner's action after the third Test between the West Indies and South Africa in Durban on Saturday.

Samuels' fast-ball action will be the subject of a biomechanical assessment by International Cricket Council technical specialists. If it is ruled that he throws rather than bowls the ball, the spinner will be banned from using this kind of delivery.

"Concerns have been raised by the match officials over the legality of Marlon's bowling action with particular reference to his 'fast ball' when viewed with the naked eye," said Roshan Mahanama, who was match referee in the South Africa-West Indies series.

"We are therefore requesting the ICC to commission a biomechanical report into the bowler's fast-ball action in accordance with the process introduced in 2005," Mahanama said.

Samuels can continue bowling until the assessment is carried out but the ICC says he runs the risk of being reported a second time if he uses his fast ball delivery.