From UFO historian Wendy Connors' collection of UFO-related recordings, including
"Cops and Saucers"

Opel Grinder, service station attendant in Socorro, NM, gives a statement to Ray Stanford regarding the object as seen by customers on the highway who stopped at his station just before Officer Lonnie Zamora came upon the UFO. 00:52 (mp3 recording)

GRINDER: Well that tourist came up here, very definitely, he came from the south.  And he said, your aircraft around here flies awfully low.  I said, well how is that, sir?  He said, well it about knocked me off the road out there.  He said it must have been in trouble, so a policeman was going to it.  So I asked him if it was a helicopter.  He said, no, it wasn’t a funny looking one (?) [probably, "if it was, it was a funny-looking one."].  So he went on about his fare, and I had to make it for the bank deposits for the bank—it was fifteen to six (5:45).  And that was the same time he was here. [Zamora gave a time of 5:50 for his encounter.]  And the next morning, well it dawned on me that the time that we met was the same time that the tourist was in here and Zamora went to that object that was on the ground there.  And I called the radio station telling them Zamora was not telling them a lie, because the tourist seen something and did something about  it (?).  And he saw the policeman officer going to the object that was on the ground which was a UFO.

Interview with Socorro gas station attendant Opel Grinder

Grinder describes tourist customers corroborating Zamora sighting, saying object passed closely over them and they saw policeman chasing after it.