MOSIER, Ore. -- A group of athletes say they were swimming in the Columbia River near Mosier when someone started to shoot at them. Of the several shots fired, according to the swimmers, some bullets came within 30 yards of the group.

“It was like someone was having a target practice,” said Mark Frost of the Columbia Gorge Triathlon Club.

Members of the group and other local athletes were swimming from Mosier to Hood River on Sunday morning when the incident happened. The group of roughly a dozen swimmers, kayakers, and paddle boarders had just passed Eighteenmile Island, roughly a mile in to the five-mile swim.

“When we got to just past the island, we started to hear gunshot coming from the hills around us,” said Frost, who was ahead of the group in a kayak. “And coming pretty close to our swimmers. I mean, within 20 or 50 yards within our swimmers.” Around 20 shots were fired, Frost says. “They looked up, and saw the bullets strike the water around us.”

Frost believes the gunfire came from a ridge above Interstate 84, in an area with some trails. “It could not have been an accident,” he said.

Responding authorities, however, didn’t find any suspects or evidence nearby.

“Within 15 minutes of the call, sheriff’s deputies and two other police agencies arrived in the area and searched the hillside, bluffs and riverbanks,” wrote the Wasco County Sheriff’s Office in a press release. “The shooting occurred on the opening weekend of youth duck hunting in this area. It is unknown if this was an intentional act or if someone was shooting irresponsibly,” read the release.

Frost said he was skeptical of the notion that duck hunters could potentially be to blame for the shooting. Based on what swimmers heard and observed, Frost believes the gunfire came from a rifle and not some type of shotgun.

“You should never be worried that somebody is going to be shooting at you for sport, for fun. It’s ridiculous,” said Frost. “Never in our lives would we be imagining we would be facing bullets raining down from above.”

The Sheriff’s Office added that the incident was isolated and that the department didn’t receive any additional calls about the gunfire. As of Monday evening, all leads in the case were exhausted, the department said. However, anyone with information on the case was asked to call WCSO at (541)-296-5454.