HOUSTON -

A Houston elementary school was placed on lockdown Wednesday morning after someone spotted a man with a gun on campus.

It happened at around 10:30 a.m. at Hartsfield Elementary on the city's southeast side. A Precinct 7 deputy was flagged down by a passing motorist at the corner of Martin Luther King Blvd. and Yellowstone with reports of a man holding a shotgun.

Deputies say the man, 36-year-old Dorian Johnson, initially entered the school without a shirt on, asking for help. When school administrators told him to leave, he went to his house, which is near the school. But a short time later, he returned.

This time deputies say he pointed a gun at a woman across the street from the school, who he thought was going to call 911 on him.

The school, which was filled with children attending summer school, went on lockdown. Parents like Hilda Duarte got a phone call. 

"I was scared, I was like what is going on there?" said Duarte.

When deputies arrived, Johnson was just a few steps away from the school. Deputies asked him to put the weapon down and after several attempts, he complied.

"I'm just grateful nobody was injured," Duarte said.

Johnson went to jail on charges of aggravated assault with a deadly weapon.