Big Island police had a rare call Monday when they received a report of an overturned mule-drawn wagon in Waipio Valley.

Police said the tongue of the wagon broke around 1:40 p.m. on Waipio Valley Road and as the driver attempted to unhitch the mules, they apparently became spooked and ran away with tourists still in the wagon.

The wagon entered a shallow river and overturned.

Four passengers were flown out of the valley by helicopter and taken to area hospitals with non-critical injuries. They were a 59-year-old woman from Japan, a 65-year-old woman from Japan, a 40-year-old woman from Japan and a 62-year-old woman from Chicago.