Officer Matthew Walsh was on patrol in Riverfront Park around 2 p.m. Monday when he spotted a pickup truck on the boat ramp "begin accelerating towards" the river, the department said.
Walsh called for backup as the truck floated off some 50 feet from the boat ramp into the middle of the river, according to police.
Walsh was trying to unmoor a boat when other officers arrived and noticed the truck was beginning to sink, authorities said.
When a girl in the truck bed shouted to police that she could not swim, Officer Edward Butterworth Jr. "immediately entered the river," police wrote. By this time, the truck was "completely submerged, and the current of the river easily could have pulled them both away," officials said.
Butterworth swam out to the pair and guided them to shore safely, the department wrote. Both victims were taken to an area hospital for observation, but neither they nor Butterworth were injured, police added.
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