Firefighters were dispatched at about 11 a.m. following a report of the collision at 50th Avenue and East Eighth Street.
A Union Pacific employee was clearing the train tracks of debris with a on-track maintenance machine when an Amtrak train struck the machine, spokespeople for Union Pacific and the Oakland Fire Department said.
The Union Pacific employee was taken to Highland Hospital with serious injuries, Union Pacific spokesperson Robynn Tysver said.
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A passenger on the train was also injured and was taken to a hospital, Oakland Fire Department spokesperson Michael Hunt said. A third person was reported to have suffered minor injuries and was not transported to a hospital, Hunt said.
One hundred to 700 gallons of diesel fuel spilled when a tank on the train ruptured, Hunt said. He said the leak has been plugged.
An Amtrak mechanical team and hazardous materials teams from Amtrak and the Oakland Fire Department were on the scene.
Amtrak train No. 531 was traveling from Sacramento to San Jose when the collision occurred, Amtrak spokesperson Jason Abrams said.
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