Former Middle Tennessee teacher Tad Cummins has been arrested in northern California and Elizabeth Thomas, the 15-year-old girl authorities say he kidnapped, is safe, according to the Tennessee Bureau of Investigation.

Just before noon, the TBI confirmed Cummins had been arrested and the girl was safe. Authorities say the pair was found at a cabin in Cecilville, which is about 120 miles south of the Oregon state line. They had been staying in a rural area about a week and a half, authorities said.

At a 3 p.m. press conference in Nashville, District Attorney Brent Cooper said, "There is more work to do to build a case for prosecution." Few details were available during the press conference about the cabin where the two were found and ​TBI agents are flying to the site to investigate and gather evidence.

U.S. Attorney Jack Smith said a federal charge has been filed against Cummins. "He is charged with transportation of a minor across state lines for the purpose of sexual intercourse," Smith said.

Elizabeth was found healthy and unharmed, but officers do not know her mental condition. She will fly back to Tennessee on a TBI aircraft and her family is awaiting her arrival, authorities said.

"Our main concern now is how is she emotionally," Cooper said. "Whether she was 'brainwashed or went willingly'? We don't know what the situation is yet."

The duo has been sought since March, when an Amber Alert was issued. They were found almost six weeks later and nearly 2,500 miles from Tennessee.

Cummins was Elizabeth's 50-year-old high-school teacher at Culleoka Unit School in Maury County, Tenn.

"We mobilized a nation in the last six weeks," said Mark Gwyn, TBI director. "When you do that, something good is going to happen because you can’t hide from millions of people."

The Cecilville cabin is located in Siskiyou County, the fifth-largest by area in California and is 10 times the size of Maury County. It is a remote area more than half covered by national forests and state lands on the California-Oregon state line. About 45,000 people live there, according to the U.S. Census.

The two were found hours after a 11 p.m. tip from a California man who said he spotted the car the two were said to be traveling in, authorities said. When sheriff's deputies arrived, they kept surveillance on the car for several hours.

At daylight they arrested Cummins and rescued Elizabeth.

"It took only one tip," said TBI Director Gwyn.

Officers ran down more than 1,500 leads and put in countless hours during the search for her, he said.

"We mobilized a nation in the last six weeks," Gwyn said. "When you do that, something good is going to happen because you can’t hide from millions of people."

Cummins is in custody in a California jail without bond, awaiting extradition to Tennessee to face charges of sexual contact with a minor and aggravated kidnapping, according to TBI.

Earlier, authorities in California said the pair were found at a commune, but those reports were incorrect.