When Valujet Flight 592 ascended for the last time in 1996, it was supposed to be for a routine, hour-and-a-half-long trip from Miami International Airport to Atlanta.

Seven minutes after takeoff, however, flight captain Candalyn Kubeck radioed a troubling message: There had been a strange sound heard on the plane, and now the pilots were experiencing electrical problems.

“We’re losing everything,” Kubeck said, seconds later. “We need, we need to go back to Miami.”

In the background were shouts of “fire, fire, fire, fire” and “We’re on fire! We’re on fire!”

Kubeck and her co-pilot managed to turn the aircraft back toward Miami, but it was too late. In the cargo hold a devastating blaze had erupted, filling the cabin and cockpit of the DC-9 with thick smoke and flames that were hot enough to melt aluminum. The plane careened downward, tilted to the right, on a final, uncontrolled descent.

At 2:13 p.m. on May 11, 1996 — less than 10 minutes after takeoff — Valujet Flight 592 slammed into the murky waters of the Florida Everglades, killing all 110 people on board. The impact was at once devastating and curious: A witness in a sightseeing plane would later tell investigators the jet seemed to vanish once it struck the wetlands, creating a deep crater in the muck and saw grass.

Crash debris haunted investigators for months as they recovered fragments of both plane and passengers from the “River of Grass.” To this day, no complete body of any of the passengers has ever been found.

“It just went to pieces,” Jacqueline Fruge, a special agent with the FBI’s Miami office, said in a statement Thursday.

The devastating crash prefaced the financial demise of one of the country’s low-cost carriers.

The National Transportation Safety Board spent more than a year working up an accident report that ruled the crash had been caused primarily by a contractor’s mishandling of the packaging and shipment of oxygen generators in the cargo hold.

The oxygen generators had been loaded without the proper safety caps, causing them to ignite in the cargo hold and trigger the deadly fire, the report said.

Investigators identified three employees of SabreTech, the maintenance contractor for Valujet at the time, who had a role in mishandling the oxygen generators, according to the FBI. Two of those employees were criminally charged but later acquitted.

However, the third SabreTech employee, mechanic Mauro Ociel Valenzuela-Reyes, fled sometime before his trial in 2000. He had been charged the year before with making false statements to the Federal Aviation Administration and the Transportation Department, as well as causing the transportation of hazardous materials.

Now, more than two decades after one of the deadliest aviation disasters in Florida history, the FBI is renewing its search for Valenzuela-Reyes, the last employee wanted in connection with the Valujet crash.

The FBI announced Thursday it was offering a $10,000 reward for information leading to the capture of Valenzuela-Reyes. The agency also released age-progressed images of what the mechanic might look like today at 48 years old.

He is described as a 170-pound Hispanic male with black hair and brown eyes and stands anywhere from 5-foot-10 to 6 feet tall. FBI investigators said they suspect Valenzuela-Reyes of living under a false identity in Chile or elsewhere in South America. He also has ties to Georgia, the agency said.

Anyone with information on Valenzuela-Reyes is asked to contact their local FBI office.

An FBI spokesman did not respond to questions sent by email or grant an interview request Friday, referring to the statement the agency had released the day before.

Fruge, who has worked for the FBI for 29 years and has been the primary agent on the Valujet case since it began, said in the statement that locating Valenzuela-Reyes would bring “closure” in one of Florida’s deadliest airline crashes.

“We’ve tried over the years to find him,” Fruge said. “It bothers me. I’ve lived and breathed it for many, many years.”

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