OKLAHOMA CITY - A false alarm shut down Tinker Air Force base.

The base was on lock down for an hour after a suspicious item was found in the car of someone trying to get on the base. That prompted a federal investigation.

The bomb squad spent hours on scene and even though it was a false alarm, authorities said they feel all precautions were necessary.

Just after 11 a.m., Tinker Air Force Base's Air Depot gate went on lockdown and the base exchange and commissary were evacuated after a woman in a white sedan drove up to the gate and attempted to gain entry.

Officials said the woman did not have proper credentials to enter and that was when security guards noticed a metal container on her passenger side.

She then apparently told the guards she found it in her yard.

"That raised some more suspicion so again in the current environment, again they took the appropriate measures just to make sure," said Ralph Monson with Tinker Air Force Base.

Those appropriate measures for any suspicious device involved calling the Oklahoma County Sheriff's Office and its bomb squad.

Bomb technicians arrived on scene then suited up to approach the sedan and investigate.

After looking around and inside the sedan for several minutes, the bomb squad discovered the device was not an explosive, and was non-threatening.

That was because the suspicious device was an old metal milk container.

Still, authorities saw every precaution necessary.

"We are a national defense asset, we have multiple strategic missions here and so anytime something happens around the gate that doesn't feel exactly right, then our security forces are going to take the appropriate measures and that's what they did today," said Monson.

The woman driving the sedan was questioned by local and federal authorities, and was taken to a local medical facility.

The eastbound I-40 off ramp at Air Depot and Air Depot gate were closed due to the investigation.