Milwaukee Brewers pitching prospect Bubba Derby was at the country music concert Sunday night in Las Vegas where the mass shooting occurred and escaped unharmed, as did friends and family members.

But the 23-year-old Derby, who spoke emotionally on a conference call Monday afternoon, said he feared he would not survive when bullets started hitting the ground around him.

"We didn’t know where the shots were coming from," said Derby, who was "about 100 yards" in front of the stage when the shooting began. "It sounded like they were on top of us. Everyone got down. We tried to get as low to the ground as possible. The first thing I did was look for my family.

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"I turned around and looked to find my aunt, and I’ll never forget the look on her face. We made eye contact and we thought we were about to die. You could hear the bullets ricocheting. It’s one of those moments where you just want to try to get out of there."

Derby, who lives in Duarte, Calif., was staying on the 28th floor of the Mandalay Bay Resort and Casino, and learned later the shooter, Stephen Paddock, was firing an automatic weapon from a room on the 32nd floor.

"We didn’t know the shooter was sniping from up top with an automatic weapon," said Derby, who attended the concert with his parents, his sister and her family, a cousin and an aunt. "My thought was that he was somewhere near the stage. That’s where it sounded like the shots were coming from.

"At first, we thought it was just firecrackers going off. We realized something was really bad when Jason Aldean sprinted off the stage. You don’t see a country artist do that. Everyone, at the same, time dropped to the ground.

"My sister and her husband were (in a) central (location in the crowd). They weren’t by the main stage. My sister wanted to look from afar and stayed back in the grass area with her husband. I went (closer) with my cousin, his girlfriend and my aunt. That changed my life forever, unfortunately."

Derby tweeted about his experience after the shooting, urging Las Vegas to "stay strong."

Derby said his parents left before the shooting began to take his 6-year-old nephew to a nearby Beatles show, sparing them the terrifying scene.

"The fact that (the nephew) wasn't there; it's so hard to think about what he would have seen," Derby said. "It would have been horrific in every sense of the word.

"It was difficult at the time because we were all spread out when everything went down. I had an angel looking out for me and my family."

When the shooting stopped for a few moments, Derby said he and his family decided to "run for our lives." But he said there was the secondary danger of being trampled as everyone else tried to do the same thing.

"We waited a few seconds and it felt like an eternity," he said. "Finally, we got up and just started running. Then we started hearing the gun go off again. It was very loud. It sounded like a bunch of firecrackers going off in a row.

"That was probably the worst feeling. Everybody was just running for their life. They were scared beyond belief."

Derby, his cousin and cousin's girlfriend, and aunt, as well as a couple he didn't know, took refuge at the House of Blues party tent at the Mandalay Bay, but opted not to remain there.

"There were a bunch of people inside, hiding and crying," he said. "We still didn’t know where the shooter was. It seemed to get louder and at that point, I said, "We can’t stay here because we’re sitting ducks." I was shouting for people to get out.

"We went out the back but on the other side of the tent there was another group of people trying to go the same route. We went down a back street and you could still hear the shooting. We just kept running and we ended up going into the Tropicana (Hotel), through where the workers go.

"At that point, I got a call from my sister. I’ll never understand fully how she was able to call me and get hold of me. We were screaming at each other, ‘Where are you? Where are you?’ They were in the Tropicana as well. So, we ran into each other, and it was then that I knew we were going to be OK."

Derby wanted to return to California on Monday but was unable to because he was not allowed to retrieve his car from what was a massive crime scene.

"I’m actually stuck here," said Derby, who was still staying in his room at the Mandalay Bay. "My truck and my sister’s car are in the valet (parking) and that lot is locked down and being investigated by the FBI. They’re not letting any cars in or out of that valet lot.

"My dad, mom, sister and nephew rented a car today to start the drive home. My brother-in-law and I are going to stay another night and then drive back tomorrow when we feel rested.

"I’ve been walking around today kind of in a haze. You see the city is pretty empty. I think people are pretty shaken up. You can tell because they have a certain look on their face like they saw a ghost. For me, personally, processing this information took a while. It’s going to be one of those things where I just have to accept what happened and try to move on from it."

Derby said it "was incredible to see" people risking their lives to provide help and treatmnt for others who were shot and wounded. And he had one thought going around and around in his mind Monday: How fortunate he is to still be alive.

"I’m sending my thoughts and prayers to all the people and families they still can't find," he said. "It’s not something I ever wanted to see. I’m extremely grateful that I was able to get out. It makes me think about the ones who weren’t so lucky. I definitely had an angel looking out for me."

Derby was one of two prospects acquired from Oakland on Feb. 12, 2016 in a trade for outfielder Khris Davis. He pitched this season at Class AA Biloxi and Class AAA Colorado Springs, going 7-1 with a 3.26 ERA in 30 appearances (14 starts).