Colombia's president said Wednesday that a Spanish journalist missing in a lawless region might not be a hostage of leftist rebels as has been widely thought in this war-weary country, but instead is reporting from inside a rebel camp.

President Juan Manuel Santos' comments provided a glimmer of hope after four days of so far unsuccessful searching for Salud Hernandez-Mora, a longtime correspondent for the Spanish newspaper El Mundo and a prominent columnist for the Bogota daily El Tiempo.

Santos said he has received information that Hernandez-Mora made contact with the National Liberation Army by choice and that the rebel group was trying to figure out how to return her safely amid the extensive search by security forces. He said he was still trying to verify the report but that it came from a trustworthy source whom he didn't identify.

"It's not completely verified but it has logic," Santos said, adding that the information coincided with information from the journalist's editors

Santos, however, said he had no information about two other journalists from local network RCN who went missing Monday while covering the search for Hernandez-Mora in the volatile Catatumbo region

Dozens of people gathered in Colombia's capital Wednesday to demand the safe return of Hernandez-Mora and the RCN journalists.

Authorities have declined to classify the disappearances as kidnappings. But speculation has been rife among Colombians that all three could be in the hands of the National Liberation Army, one of several rebel groups operating in that region.

Gen. Alberto Mejia, the head of the army, said troops on the ground engaged in combat with an unidentified group Tuesday.

As part of the search, authorities have dropped more than 30,000 pamphlets from the air over Catatumbo seeking information about Hernandez-Mora's whereabouts. They also offered a $30,000 reward.

Hernandez-Mora, who has lived in Bogota since the 1990s and also has Colombian citizenship, is one of the South American nation's most influential journalists. Admired and reviled in equal measure for her opinion columns frequently critical of the Santos government's peace efforts, even her detractors in the government acknowledge her courageous reporting in violent areas where the state has almost no presence.