Gwinnett police are praising a mother who took action when her child noticed suspicious activity at an apartment playground.

Police arrested a man who a witness says exposed himself to kids outside a Lawrenceville apartment complex Sunday evening, according to Channel 2 Action News.

A young girl told her mother she saw a man on a nearby staircase performing a sex act on himself while staring at the kids at the apartment complex playground, according to police.

Gwinnett County police spokesman Cpl. Deon Washington said the man jumped the property fence after the mother called 911.

Responding officers who spoke with witnesses arrested Granger Martin on the third floor of one of the apartment buildings.

"When the officer approached the male, his pants were down to his ankles and the male was heavily intoxicated and looked as though he was lost," Washington said.

Martin, who lives a short distance from the Landmark at Coventry Point complex, told police a number of stories to explain why he was on the gated property.

“He stated that he was working out, that he was waiting on someone,” Washington said.

Police say it's a classic example of kids knowing they should find an adult when someone is doing something wrong or something that makes them feel uncomfortable.

“We live in crazy times," Anthony Smith, a resident of the apartment complex, said. "You got a lot of nutcases out here."

Martin remains in the Gwinnett County Jail facing a number of charges including child molestation, public indecency, loitering and prowling and consumption outside premises, a county ordinance for public intoxication.