OAKLAND (CBS SF) – Family members and friends are worried about an Oakland couple who appear to have disappeared during a bike trip in South America last month.

Garrett Hand, 25, and his girlfriend, Jamie Neal, left on their bike trip in late November, and at the end of January all communication stopped, Hand’s sister Larkin McGowan said Monday.

She said there has been no financial activity on the couple’s bank accounts or credit cards since Jan. 25.

“That’s the big alarm,” said McGowan, who lives in Concord.

The couple, who McGowan described as avid bicyclists and well-traveled, have been documenting their trip online. Social media posts dropped off around the same time the financial activity stopped, she said.

The last post on Neal’s Facebook was on Jan. 23, when the pair arrived in Cusco, Peru.

Hand, a commercial fisherman in the Bay Area, posted in Spanish on his Facebook page from Cusco on Jan. 25 that the next stop of the trip would be Pucallpa, Peru, if the couple could find a bus.

Neal, who is in her 20s and works at the Pedaler Bike Shop in El Sobrante, had been in touch with her coworkers through the end of January, shop mechanic Mark Lindgren said.

The shop has pooled together a $3,000 reward for any information that will help locate the couple.

Lindgren said Neal had taken time off work for the trip, and that regular customers and colleagues are concerned.

Donations for the couple’s families can be made at any Mechanics Bank by mentioning Hand or Neal, Lindgren said.

On Feb. 13, the U.S. Embassy in Lima, Peru, posted an emergency message warning of a potential kidnapping threat in the Cusco area.

“The Embassy has received information that members of a criminal organization may be planning to kidnap U.S. citizen tourists in the Cusco and Machu Picchu area,” the message reads.

The threat is listed as credible through the end of February.

KPIX 5 has learned the couple may have been spotted as recently as last week by a proprietor of a boarding house in the town of Iquitos.

Belinda Bueno, who operates Hospejade Begonia said in a phone interview Monday night that she met the couple and had a long talk with Garrett about his tattoos. She said the couple stayed at the hostel twice for as many as seven days total and that they were there as recently as February 16th.

Bueno initially said in the interview she thought the couple was headed toward Ecuador, but later said they might still be in the area on a spiritual retreat.

Authorities have not confirmed the couple was in the area of Iquitos.

McGowan said the families were working with the U.S. Embassy and local authorities.

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