Early on the morning of April 25, Los Angeles County Fire Department Engine 90 responded to a roaring blaze at the Cheque Tire Shop in South El Monte.
When the firefighters pulled up to the scene at 5:33 a.m., they were horrified by what they saw.
Rodrigo Gonzalez, 17, his clothes on fire, was desperately trying to escape from behind a locked, chain-link fence.
Fire Inspector Christopher Reade said a colleague immediately grabbed a rotary saw and attacked the gate's lock. The fire was so hot it melted a plastic tarp off the fence and left the firefighter with second-degree burns.
Before the gate could be opened, Gonzalez had retreated to the back of the shop and wasn't seen alive again.
"You're a firefighter because you want to save people," Reade said. "When you're not able to save someone, it hurts."
In all, 55 firefighters fought the blaze that morning, and they found the bodies of Gonzalez and two other teenagers in the ashes of the shop.
It quickly became apparent that the fire was no accident. Investigators discovered that a birthday party had taken place at the business hours before and that the fire was caused by three Molotov cocktails thrown at the building.
It took some time, but detectives now believe they know what happened and why. Authorities allege that four men who attended the party later returned with the explosives because they were angry after an altercation.
"They returned for vengeance for a perceived slight," said Deputy Dist. Atty. Sean Carney. "These guys were pissed off and retaliated, and it wasn't pretty."
It isn't clear whether the arson suspects simply meant to torch the shop or if they knew that the teens were inside and intended to kill them.
In any event, German Monrreal, 19; Mario Godina, 19; Estevan Castillo, 20; and Roberto Fuentes, 20, have been charged with three counts of murder, one count of arson causing great bodily injury, and one count of use of a destructive device and explosive with the intent to injure a person and destroy property. If convicted, they could all get the death penalty.
They all appeared in court two weeks ago, when their arraignment was continued. They will appear again Thursday.
Their attorneys either declined to comment or could not be reached.
As the case developed, family members of the victims have struggled to cope with the loss of loved ones who were just entering adulthood.
Gonzalez often worked at the tire shop, which was owned by his father. His friends called him "Rigo" and remembered him as gregarious jokester who loved to ride horses. Carlos "Christopher" Jimenez, 17, was determined to graduate from high school and become a lawyer so he could help underprivileged kids.
Destiny Aguirre, 18, had two daughters, ages 1 and 3, but that didn't stop her pursuit of a high school diploma. She had just received her driver's license and was taking independent studies to get her degree.
Her mother, Lena Aguirre, 36, wishes she had her daughter back to hold and laugh with. The girl loved doing people's makeup. She hoped to attend Mt. San Antonio College and get a degree in makeup artistry.
"She made the house lively," Aguirre said, fighting tears. "I just want everyone to know that she was the best daughter."
Video from a surveillance camera the morning of the attack shows the four suspects piling into Fuentes' gold 2002 Nissan Altima, police said. They had all attended Jimenez's birthday party the night before. Jimenez was turning 18, and Gonzalez was hosting the celebration.
At the party, some members of the El Monte Flores gang hassled the four suspects, and one of them had his gold chain stolen by the gang members, according to two sources familiar with the investigation.
After the party cleared out, Gonzalez, Jimenez and Aguirre went to sleep inside the shop. But first they locked the gate to the grounds, which faces Santa Anita Avenue and is surrounded by a concrete block wall and chain-link fence.
Then, just before 5:30 a.m., police say, Monrreal, Godina, Castillo and Fuentes set the shop ablaze.
"When you throw a Molotov cocktail into a business like that, an automotive tire shop with all kinds of accelerants, it makes a very bad, intense fire," Sheriff's Lt. Victor Lewandowski said in early July.
Authorities said three of the four suspects fled to Mexico, where they were captured in July. A Sheriff's Department spokeswoman said the combined reward of $30,000 offered by the city of South El Monte and the Los Angeles County Board of Supervisors drew a tip and "played a significant role" in the arrests.
A phone call from those fateful hours plays over and over in Lena Aguirre's head. Around 2 a.m., her daughter called her.
"She said, 'Mom, can you pick me up?'" Aguirre said. "I said, 'yes,' but then she hung up."
Her phone needed charging, so she hung up, her mother said. Nothing sounded wrong. Her daughter just needed to charge her phone and wanted to come home.
"I thought she was going to call me back," Aguirre said, "but then she never did."
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