Captured in Colombia (Parker Twins Series, The)

Everyone is on high alert, but Justin and Jenny Parker aren't really concerned until Uncle Pete, a high-level executive for Triton Oil, is kidnapped--right from under their noses! His kidnappers, Colombian guerrillas, want to trade Uncle Pete for some of their men who are in jail for bombing a Triton Oil facility. Now the twins must not only decide whether they can trust a new friend, but they have to rescue Uncle Pete before a nearby volcano erupts.