CNN  — 

Master Sgt. David Royer stood upright with his interlocking hands in front of him Thursday as he matter-of-factly recounted how he rammed his truck into an active shooter before heading home to hug his kids, mow the grass and have dinner.

The military police officer based at Fort Leavenworth likely saved “countless lives” with his quick action one day earlier when a gunman opened fire on a busy bridge connecting Kansas and Missouri, police said.

“I don’t necessarily myself feel like I’m a hero,” Royer said. “I feel as if most people in my situation would have done the same thing. There was nothing else I could do… I knew lives were in danger.”

The gunfire erupted late Wednesday morning on the Centennial Bridge when a man armed with two weapons stopped his vehicle, stepped out and began shooting, according to Leavenworth Police Chief Patrick Kitchens.

One motorist was wounded.

Soldier ‘assessed the situation very quickly’

Master Sgt. David Royer said he "took the only action possible that I felt I could take."

Royer was sitting in his truck, chatting with his fiancee via speaker phone during heavy construction traffic on his way home. He saw a man outside a car in front of him.

“As I was talking to her, the man pulled up a rifle and started aiming… and began to shoot off some rounds,” Royer recalled.

Royer told his fiancee to call 911 and hung up.

“I assessed the situation very quickly, looked around and took the only action possible that I felt I could take,” he told reporters. “I accelerated my truck as quickly as possible and struck the active shooter and pinned him underneath my truck.”

The motorist wounded by gunfire is also a soldier at Fort Leavenworth, the police chief said. The gunman was also injured. Both men were in serious but stable condition at a hospital, according to Kitchens.

“What was a very, very dangerous situation fortunately was ended quite quickly and … very likely countless lives were saved by the person who intervened and helped,” Kitchens said.

The shooter randomly fired at cars

Royer said his training as a military police officer during 15 years in the Army and adrenalin took over when the shots rang out.

After plowing into the gunman, Royer said he came out his truck but didn’t immediately see the shooter. He walked around and saw the rifle on the ground.

“I assumed he was not a threat anymore,” he said.

The gunman was trapped beneath the truck. Royer tried to assess the man’s condition. The shooter mumbled but Royer couldn’t understand him. He saw a pistol when he went to shut off the car’s engine.

Police work the scene of a shooting on the Centennial Bridge in Leavenworth, Kansas.

Within minutes, local law enforcement arrived at the bridge. Some motorists thanked Royer.

“After the incident was over I was pretty calm,” he said. “But when I got home I just wanted to get everything back to normal – get to my kids, give them a hug and then I mowed my grass, ate dinner and spent time with my family.”

Two cars on the bridge were hit by gunfire. The passengers weren’t hurt. Kitchens said the gunman appeared to have randomly opened fire on cars.

Police were called about 11 a.m. Wednesday, as Kansas transportation department personnel did work on the bridge. The initial report was of shots fired in a potential road rage incident, Kitchens said.

“As the investigation unfolded, we learned this was an active shooter with multiple weapons on the bridge firing at cars with no particular association,” he said.

The shooter had a handgun and a semiautomatic rifle, the police chief said.

The motive is under investigation. Royer wasn’t hurt.

Police have not commented on criminal charges against the gunman.

‘I had a lot of good times in that truck’

The military veteran hails from a small town in Ohio. His father is a truck driver who has stopped to pull people to safety at highway wrecks. His mother is a feisty “smaller woman” who once stood up to man who was 6 feet, 5 inches tall to protect his brother, he said.

“They’re very strong and they’ve shown me – do not let fear take control of you,” Royer said.

Royer’s 2014 Chevrolet Silverado sustained extensive damage.

“First vehicle I ever owned in my name,” he said. “I had a lot of good times in that truck.”

The gunman, who was not identified, resides in Platte County, Missouri, according to Kitchens.

The Bureau of Alcohol, Tobacco, Firearms and Explosives was tracing the weapons, CNN affiliate KMBC TV reported.