Police haven't said what was in an 18-wheel truck parked since Monday at a Hixson Pike storage business, but it wasn't explosives.

Authorities on Wednesday evacuated 250 homes within 1.5 miles of Ark Care Storage near the Thrasher Pike intersection after they suspected the truck held a bomb, Hamilton County Sheriff's Office spokeswoman Janice Atkinson said.

Hamilton County Sheriff Jim Hammond said explosives-sniffing dogs "hit on something" in the truck, but he would not elaborate.

No information will be made public on the truck's driver or its contents pending an FBI investigation, Ms. Atkinson said. The truck had a Mississippi license plate and is registered in Texas, officials said.

Managers of Ark Care Storage, at 7327 Hixson Pike, told police the driver parked the truck Monday and refused to show identification while filling out paperwork.

When the truck still hadn't been moved by 11:30 a.m. Wednesday, the managers called police.

The Chattanooga Police Department bomb squad and agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives examined the truck, drilling a hole to see what was inside.

The contents of the truck "presented no danger to the public," Ms. Atkinson said. The roadblocks were lifted at 4 p.m.

Bill and Brenda Rock waited in the church parking lot Wednesday afternoon for the signal they could go home.

Mrs. Rock was at the grocery store when she heard about the evacuation on the radio. Knowing her husband was home, she said, "I called him and said, 'You need to leave.'"

Speaking with reporters at Burks United Methodist Church, about a mile from the storage business, Sheriff Hammond said the driver had expressed "different views" while filling out paperwork Monday. He would not elaborate on the driver's description or whereabouts.

The sheriff and Hamilton County Mayor Claude Ramsey said that the dogs' reaction meant there was "enough there to raise the awareness of law enforcement."

Bomb squad head Sgt. Al Tallant said he could not comment on details involving the truck, but he said police must take precautions when they find indications that explosives could be present.

"We don't want to block off the roads and inconvenience people either," he said. "But the fact is, if we get something suspicious, we want to make sure we know what we have. We want to keep everybody safe."