(CNN) -- Imagine the police dog handler's surprise when the canine snapped at the ground, and the ground cried out.

That was how a police dog found a camouflaged burglary suspect, authorities in Washington County, Oregon, said Thursday.

The dog alerted his handler that he smelled something on the ground about a half-mile from the Rice Northwest Museum of Rocks and Minerals in Hillsboro, Oregon, a Washington County Sheriff's Department spokesman said.

The movement of the suspect spooked the dog, who bit the ground, which "cried out in pain," said Sgt. David Thompson.

The ground turned out to be a man dressed in a ghillie suit, made to resemble trees and earth, he said. Military snipers and hunters often wear the camouflaged suit.

Gregory Liascos of nearby Portland, Oregon, was charged with burglary and criminal mischief, Thompson said. Liascos, 36, has no criminal history and was lodged in the Washington County Jail pending a hearing, authorities said. He was treated on the scene for the dog bite on his shoulder blade.

Nothing was taken from the museum, said Thompson. He theorized the suspect was perhaps interested in a collection of gold nuggets.

In an unrelated case, authorities in April arrested a man suspected of stealing the nuggets. Most, perhaps all, of the gold was recovered. The gold was valued at more than $250,000, the Oregonian reported.

The camouflaged burglar apparently had been working on entry to the museum in stages, authorities said.

A museum caretaker first alerted deputies Wednesday that he found a hole secretly cut in the wall of an exterior bathroom, which had no direct access to the museum. The caretaker had noticed dust over a couple of days and eventually found a hole where the bathroom met an elevator shaft, officials said.

Authorities put in unspecified equipment that would alert them if there were activity again in the bathroom of the museum.

Deputies got an alert and arrived on the scene about 5 a.m. Thursday and spotted a bicycle and backpack on the grounds, Thompson said. A K-9 team from Beaverton Police found the suspect, he added.

Security within the museum would likely have alerted police if Liascos had entered the interior of the building, Thompson said.

The museum, which once was a residence, is popular with school groups.

CNN's Phil Gast contributed to this report.