(NEW YORK) -- Two young bike enthusiasts from California have disappeared while on a biking "trip of a lifetime" through South America, according to the U.S. State Department.
Jamie Neal and her boyfriend, Garrett Hand, both 25, embarked on their journey at the end of November, or early December, according to Neal's boss, Jeff Jerge. Neal works at the Pedaler, Jerge's El Sobrante, Calif., bike shop.
"I'm beyond worried," Jerge told ABCNews.com. "I'm super concerned."
Jerge said that Neal and Hand had known each other for a while and began dating and planning their South American trip last summer.
"It's kind of like it was a dream trip for them," Jerge's wife, Kim Jerge, told ABCNews.com. "It's their first big adventure."
Neal has worked at the bike shop for more than two years. Hand is a fisherman in Alaska.
"They wanted to originally ride from here to South America, and we thought going through Mexico was particularly dangerous, so we talked to them about skipping that, and they did decide to fly down to South America and start their trip there," Jeff Jerge said. "We all felt it was potentially dangerous."
As the couple cycled through the continent, they frequently posted updates and photos on Facebook, chronicling their journey. They posted photos of camping, the wildlife and the people they met along the way.
The last post was on Jan. 25 and said, "Finally found Kraft Mac 'n' cheese in South America! Stoked LOL." The couple has not been heard from since.
Jeff Jerge called Neal "very knowledgeable and an extreme cycle lover" and a talented mechanic.
"They had all the right gear," he said. "[The trip] was really well-planned and thought out in terms of the bicycling part."
The U.S. State Department said that according to their families, Hand and Neal had been traveling from Cusco to Lima, Peru, and were expected to arrive in Lima on Jan. 26.
"There's potential that they could be out of service and there's potential they could have just lost contact, but the frequency of their posts before Jan. 25 was pretty close to one another, and certainly there's never been a gap like this," Jerge said. "It really doesn't look good."
A State Department official confirmed to ABC News that the couple had not been heard from in almost a month.
"The U.S. Embassy in Lima is aware of the two U.S. citizens who apparently went missing while on a cycling trip in Peru," a State Department official said in a statement to ABC News.
"Consular officers from the U.S. Embassy in Lima are in contact with the families and Peruvian authorities, and are providing all appropriate consular assistance," the statement said. "The Peruvian authorities provided us all assurances that they will do everything possible to locate this couple. Embassy officers will continue to provide all appropriate consular assistance and to follow developments closely."
On Feb. 13, the U.S. Embassy in Peru issued a warning to Americans to beware of a kidnapping threat in the Cusco area from a criminal organization, but the State Department official could not confirm that the couple had been kidnapped, saying only that an investigation was under way. The Cusco area is near Machu Picchu, and is a popular destination for tourists.
Jerge's bike shop has so far raised $4,000 as a reward for information on the couple.
"We don't know what to do," Jeff Jerge said. "What do you do when people are that far away and you're trying to help them?"
Flyers in English amd in Spanish have been made, and Jerge has made contact with other bikers in Peru to post the flyers. He is planning on reaching out to his distributors who have offices around the world to help get the word out.
"Both of them are just great people, and Jamie is just a good-hearted, fun-loving person with a lot of energy," Kim Jerge said. "She rode her bike to work from Oakland, which is about a 25-mile commute every day. She's a hard worker. She worked for us for two-and-a-half years. She's part of the family."
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