Hundreds of people on horseback are helping keep Houston's big airport safe.

The Airport Rangers Program, created in December 2003 to increase airport security, has stopped potentially dangerous things from happening at Bush Intercontinental Airport on several occasions, officials said.

Each day, hundreds of volunteers on horseback, including off-duty law enforcement officers, work to keep the perimeter of the 13,000-acre airport safe.

"We are really unpredictable. There's no way to tell when we are going to be out there, who's going to be out there -- and for those people who want to come out and do misdeeds, (it) makes it hard for them to know when to do them," said Kelly Baber, an airport ranger.

The Airport Rangers are required to go through a security background check before they are cleared to have access at the airport.

Baber has been patrolling the airport for years and said his group has seen just about everything.

"We have seen some people target-practicing right under the runways at the airport on some county land and that definitely is not allowed. We had one gentleman who called in a car that was getting stolen," Baber said.

The group is looking for more volunteers. For more information, visit www.fly2houston.com/airportrangers.

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