The victim was hit by a northbound train at 4:18 p.m., BART police Lt. Tyrone Forte said. Train service was immediately shut down, the station was closed and power to the station was cut.
The train remained on the northbound track after electricity was cut, which initially made it difficult for rescuers to get to the victim, who was believed to be either on the tracks or under the platform, Hayward fire Capt. Thor Poulsen said.
Power had to be shut down to protect rescuers and potentially the victim from electrocution, but that also meant that it took over an hour to move the train out of the way to get to the victim, Poulsen said.
Eventually the train was moved and the victim, a man between 40 and 50 years old, was found lying facedown between the two main tracks. He was pronounced dead at the scene, Poulsen said.
The station reopened at 7:06 p.m. and BART is still recovering with delays systemwide, BART spokesman Jim Allison said.