SAN ANTONIO -

A man accused of attempting to pull over another driver and impersonating a police officer is in jail.

It happened Wednesday near Poe Middle School.

San Antonio Independent School District officials said an SAISD officer was patrolling the area there when he saw a yellow Ford truck with flashing red and blue emergency lights speed by the school.

"He observed a man driving a truck that had flashing emergency red and blue lights driving aggressively behind a Ford explorer with a female driver," said Leslie Price, a spokesperson with SAISD. "He was honking and attempting to have her pull over."

According to the police, when the campus officer witnessed that, he activated his own lights and siren and eventually stopped the man at the 600 block of New Braunfels Avenue.

When the officer asked the man if there was an emergency, the driver, who has been identified as Cesar Perez, 51, said he was a police officer and handed him a Stratford Career Institute Security Diploma Card.

Perez also told the officer he had a gun under his seat and handed him a copy of a Blackhawk Security Firearm Proficiency Certificate of Completion.

"We don't know what this man was going to do, but it's very concerning," said Price. "It's very disturbing behavior and we are just very grateful that we have very observant watchful officers and this particular officer was able to take action."

The campus officer retrieved the gun and Perez was arrested immediately.

Karen Simms, a parent at Poe Middle School, said she is glad Perez was caught before he had a chance to hurt the woman or any students.

"It's very scary," said Simms. "I'm truly happy that the officer was alert to see the man that stopped the woman because there's no telling what would have happened."

As for the woman in the explorer, SAISD officials said she was not hurt and that she just drove off when the  officer came to her aid.

As for Perez, he faces charges of impersonating a public servant, false identification as a peace officer and unlawful carrying a weapon.

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