A Ruger .380.

A flasher allegedly got more than he bargained for when he approached a woman at a lake in Washington state this week: a Ruger .380 pointing back at him.

“I put the magazine in my gun. I cocked it,” the woman told The Daily News online. “I said, ‘You need to leave or I’ll shoot you. I’m going to blow your brains out.’”

The gun reportedly had the intended effect.

“Oh, [expletive]!” the man declared, according to the paper, before running away.

The 35-year-old woman was at Lake Sacajawea in Longview, Wash., with her 6-year-old son and a dog Wednesday evening when the man approached, police confirmed to NBC News.

He allegedly sat down and began performing a sex act and said she should watch.

It was at that point that she pulled out her gun.

After the man ran away, she sent her dog, a Norwegian Buhund Hound, after him, police said. The dog cornered him, and when she called the dog back, the man disappeared into the darkness.

The alleged flasher is described as a “white male in his early 20s with short dark-blond hair and wearing a gray hoody and dark blue jeans,” the paper reported.

Detective Kyle Sahim said police are actively investigating the incident, including whether it is connected to another reported flashing in the area.

"Not a common event in Longview," Sahim said.

For more, visit The Daily News online

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