The murders occurred at the Bay Cities Auto Auction yard on Addison Way.
"It did come in as a possible hit and run with a victim down in the middle of the street," Lt. Chris Orrey of the Hayward Police Department said. "When patrol officers arrived, they saw trauma to a person down in the street and the fire department responded and the paramedics did confirm that the victim was deceased."
Bay Cities security guard John Horton identified the employee as the overnight security guard at the lot, which is a 24-hour operation. Horton said the unarmed guard was just one year away from retirement.
A second victim, another man, was found dead inside the cab of a car transport truck that was parked in an adjacent lot. His truck was surrounded by several vehicles, with their windows smashed, according to another truck driver who spent the night in the lot.
"I saw the broken window on his left, on the driver's side and then the chain on it, so probably someone was attacking him, I don't know," he said.
The truck driver explained that drivers typically arrive late in the evening and spend the night in the lot, before picking up a load of cars for transport first-thing the next morning.
Police would not say how the two victims were killed.
Company security guard John Norton says the area where the murders occurred is covered by surveillance cameras.
"There's cameras right there in the vicinity and they go all different directions; I'm sure it might be on camera," he said.
A search of the surrounding area did not turn up any suspects. Investigators did say robbery is one possible motive for the murders, but did would not reveal if any cars or other property was taken from the lot.
Car dealer Eric Murguia says there is only one thing to steal here.
"Cars, that's it; there's no money in any of this," he said.
The murders are the fourth and fifth in Hayward already this year. Last year, the city had a total of seven homicides.
Anybody with information about this incident should call Inspector Mike Woods, Inspector JP Guimaraes or any available inspector or detective through the Crime Stoppers line at 510-293-7197. Crime Stoppers of Southern Alameda County is offering a reward of up to $1,000 for information that leads to an arrest.