POMONA, Calif. -- His whole career, Pomona Police Officer Greggory Casillas had worked up to this day: His last field training shift before he could finally ride solo.
The shift marked the end of his "ghost phase" of training, a two-week stretch when his training officer wore civilian clothes, mostly observing to make sure he was ready. Casillas told a co-worker that he could not wait to be on his own.
"He was so excited," said Allison Campos, a jailer with the Pomona Police Department. "He really wanted it. I've never met someone so eager to become a police officer."
Then tragedy struck.
During that Friday shift, a reckless driver led officers on a pursuit that ended with a crash. Casillas, 30, followed the driver into a Pomona apartment complex, where the man was barricaded in one of the units.
As Casillas approached, he was struck by bullets fired from behind a door. He was taken to a hospital, where he died. A second officer who was shot in the face trying to save him was released from the hospital and is recovering from his wounds.
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The suspected shooter was arrested on suspicion of murder and attempted murder and is due in court this week.
More than 300 mourners gathered outside Pomona police headquarters Sunday night for a candlelight vigil, where officers wore black mourning bands with the number "16" -- Casillas' badge number -- over their badges.
"Losing Gregg has ripped a hole in the hearts of his family and members of this department," Pomona Police Chief Michael Olivieri said at the vigil.
Colleagues remembered the 6-foot-4 Casillas as a gentle giant, a hard worker who loved to joke around with and motivate his co-workers. A father of two small children, he was just starting to build a family with his wife, they said.