KAMPALA, Uganda — An American woman touring one of Uganda’s most popular safari destinations was kidnapped with her local guide on Tuesday evening and held for $500,000 in ransom, the authorities said.

Ugandan security forces said on Wednesday that they were searching Queen Elizabeth National Park, the site of the abduction, for the two victims and their kidnappers.

The kidnapped tourist is Kimberly Sue Endicott, and the guide is Jean-Paul Mirenge Remezo, according to an official with Wild Frontiers, the safari company with which they were traveling.

The park, home to more than 600 bird species and some 2,500 elephants, is generally regarded as safe for tourists.