From Kyle Hopkins in Anchorage --

Authorities evacuated about 50 homes Friday night in the Trapper Creek area after the discovery of roughly 550 pounds of unstable explosives in an abandoned station wagon, troopers say.

An explosives team from Joint Base Elmendorf-Richardson destroyed the cache at 2 a.m. No one was injured, troopers say.

The explosives had been in the car since the mid-1990s when a man who owns the property moved them there from a nearby railroad box car, said troopers spokeswoman Beth Ipsen.

The property owner has been living in the box car, Ipsen said.

The incident, which rallied several government agencies and displaced dozens of families, began when the man asked an Alaska Wildlife Trooper to his property for what at the time were unknown reasons, troopers said.

“(The property owner) just called him and said, ‘Hey, can you come out here and talk to me,’” Ipsen said.

The trooper arrived at about 2:45 p.m. Friday at mile 3.5 of Petersville Road, according to a trooper report. The property owner showed him the car, Ipsen said.

A troopers report described the cache of material as dynamite. The materials included ammonium nitrate and nitroglycerine, Ipsen said.

"It was approximately 15 to 20 years old and had crystallized," she said.

"It was a concern so the wildlife trooper called the Air Force EOD team on Elmendorf," she said.

The team arrived at 8 p.m. and deemed the explosives unstable. Authorities soon evacuated about 50 homes within about a mile of the car, Ipsen said.

Trapper Creek Elementary, located just outside the evacuation area, served as a temporary shelter for evacuees. A trooper helicopter flew above, making sure everyone had left the area, troopers said.

Neighbors were allowed to return to their homes after the explosives were destroyed, Ipsen said. A neighboring home sustained minor damage, including busted windows, in the blast.

“There was nothing left of the station wagon,” Ipsen said.

Ipsen said she didn’t know the identity of the property owner and likely wouldn’t name him if she did know. That's because he has not been charged with a crime, she said.

“We have notified federal authorities. I don’t know if they’re going to look into it,” Ipsen said.

Troopers, Mat-Su Borough emergency personnel and the Division of Forestry helped with the evacuation. Trooper and Mat-Su officials made the call to detonate the explosives after a final sweep of the area by helicopter, Ipsen said.

This is a developing story. Check back for updates.

Contact Kyle Hopkins at khopkins@adn.com.