Ethiopian Paralympic runner Tamiru Demisse crossed his arms above his head in a political protest as he went over the finish line in Rio.
Tamiru came in second in his 1500m T13 race for visually impaired runners.
The gesture echoed the one made by compatriot Feyisa Lilesa at the end of the Olympic marathon.
It refers to protesters from the Oromo ethnic group in Ethiopia who have been involved in months of demonstrations as they demand greater political rights.
Feyisa is now in the United States after saying it was not safe for him to return home.
Tamiru's 1500m race was also notable for the fact that the top three runners, Algeria's Abdellatif Baka, Tamiru and Kenya's Henry Kirwa, all ran times faster than the winner of the Olympic 1500m race.