(CNN) -- There's no such thing as an off-duty cop. At least if it's Justin Rogers, there's not.
The police corporal from Pinole, California, was just capping off a family vacation in Hawaii. He was going through security at the Honolulu airport last Saturday, when he felt compelled to spring into action to stop a rowdy security breach.
He had just taken his shoes off to go through the body scanner when he heard a "loud crash" off to his side, he told CNN affiliate KTVU.
"When I turned around, I saw a woman with her arms flailing, screaming at this TSA agent." He turned back around, thinking security officers would handle the ruckus.
They didn't at first.
The disturbance turned into fisticuffs, TSA surveillance camera video revealed. The woman, who was trying to force her way through the security section for flight personnel, lit into the female TSA agent who was blocking her path.
"The next thing I know, I heard what I thought was skin to skin contact, like somebody getting punched," Rogers said. "Sure enough, she was punching her."
Time for action
He saw that the agent's colleagues were far away from her, so he thought he'd better help out.
He bounded over a waist-high security barrier and with a quick swoop and a professional takedown separated the assailant from the agent and immobilized her on the floor.
Other TSA agents came running.
In comfy shorts, T-shirt and ankle socks, Rogers didn't look much like an officer of the law. "I was in relaxed mode." His wallet and presumably his ID had already gone through the X-ray machine.
But his immobilization posture over the suspect looked professional, and he quickly told agents who he was.
"I held up my hand and said, 'I'm a police officer; I'm a police officer,' because I was worried maybe they'd think I was assaulting somebody."
They believed him. In fact, TSA later issued a statement lauding Rogers for his "swift actions" in "immediately" subduing the individual and preventing the TSA officer from being hurt any more.
An airport policeman pulled out a pair of cuffs, and Rogers helped him secure the suspect's wrists. The woman was arrested and charged with assault, CNN affiliate Hawaii News Now reported. She was homeless and had been wandering the airport.
"That was pretty much the end of story," Rogers said.
CNN's Jim Barnett contributed to this report.