The AIU said in a statement that Chemusto had returned an adverse analytical finding for prohibited substance "19-Norandrosterone (a Metabolite of Nandrolone (19-nortestosterone) or Nandrolone precursors)".

The sample was collected at Nairobi's Kip Keino Classic in May, where Chemusto clocked a personal best of 4:01.79 to win the women's 1,500 metres.

The ban will be backdated to July 13 2023, and Chemusto's competition results from May 13th onwards will be disqualified.

The AIU also announced an 18-month ban for Egyptian long-distance runner Ahmed Saber Mohamed Bakry (38). Ethiopia's Zerfe Wondemagegn (21) and refugee athlete Fouad Idbafdil (35) were provisionally suspended for the "presence/use of a prohibited substance".

Morocco-born Idbafdil was part of a six-member Athlete Refugee Team that competed at this year's World Athletics Championships in Budapest.