A US jockey is in police custody after a trainer was shot at the Delaware Park race track on Wednesday.

US publication the Paulick Report stated the trainer Saul Matos and jockey Ruben Rojas became embroiled in a verbal altercation in the stabling area at the track.

State police told local news media outlet Delaware Online that Rojas was allegedly in his vehicle arguing with the trainer when the jockey pulled out a gun and shot Matos in the stomach.

Rojas fled the scene before police alleged he threw the gun into a creek that runs adjacent to the Delaware Park track.

Police arrested Rojas without incident a little more than an hour after the alleged incident before recovering the gun.

The trainer remains in hospital with non-life-threatening injuries while Rojas was unable to raise the bail amount before he was taken to a local jail to await a court hearing on three charges.

6ABC News reported the duo were arguing about a woman when the trainer was shot.