U.S. Park Police have two people in custody after conducting an operation in Montgomery County, Maryland, on Wednesday. They stopped searching for a third person in an operation where U.S. Immigration and Customs officials were seen. U.S. Park Police said officers were conducting commercial vehicle enforcement on Clara Barton Parkway alongside federal law enforcement partners Wednesday morning. Law enforcement vehicles were at the Glen Echo turnaround during the morning rush hour, stopping vehicles that are not allowed to drive on the parkway. Video shows three men running up the inbound side of the Clara Barton Parkway away from the Glen Echo turnaround, leaving a white panel van with ladders on top by the side of the road. Officers are seen in video running after the men, followed by a police SUV driving against inbound traffic. The men disappeared into the woods that border the Potomac River. Two people are in custody after fleeing feds in Maryland, police say. Video shows officers in ICE vests. Rescuers searched the Potomac. News4's Paul Wagner reports Jake Schaller, who is married to News4’s Melissa Mollett, was sitting in traffic approaching the turnaround when he noticed the men running toward him. Maryland “I saw two men probably in their 30s, both Hispanic, running toward me up the Clara Barton Parkway, and they were both running and they both had their right hands on their right pockets, trying to keep something in their pockets, which I thought was weird,” he said. “And I started looking around, and then came a third man kind of running the same way, kind of up Clara Barton Parkway, except as he kind of got toward my car, he took a left and went down into the bushes and trees toward the canal.” Montgomery County Fire and Rescue was called because it was believed that some of the people who fled the stop may have jumped into the Potomac River. MCFRS was searching the river between Lock 7 and Lock 10. Within an hour or so, radio from firefighters on the scene indicated two men were in custody but a third got away. U.S. Park Police confirmed they were working with “federal law enforcement partners” at the Glen Echo Turnaround but didn’t say it was ICE. Video shows federal officers wearing ICE vests in a pickup truck at the scene, but their involvement is unclear. News4 reached out to ICE but hasn’t heard back. Commercial vehicles are restricted on National Park Service roads, including the Clara Barton Parkway. According to WTOP, police activity caused delays on Clara Barton Parkway inbound near MacArthur Boulevard and the Glen Echo turnaround. Montgomery County Executive Marc Elrich said it wasn't the first time there's been reports of ICE activity on Clara Barton. “This is another dark chapter in the work Donald Trump does,” he said. News4 sends breaking news stories by email. Go here to sign up to get breaking news alerts in your inbox.