As the incursion into Baghdad heated up Thursday, Gov. Mark Sanford poised the state for potential threats while local governments tightened security, reviewed emergency plans and increased patrols of facilities sensitive to terrorist attacks.

Sanford boosted the state's security level from four to three; level one is the highest threat of imminent danger. The move activated the state's Emergency Operations Center, with limited staffing, and put members of the state's Emergency Response Team on standby. Will Folks, the governor's spokesman, could not disclose additional security measures.

Public safety officials in Horry County reviewed response protocol, confirmed points of contact and stayed in touch with state agencies.

Horry County also marked the day by hiring a full-time terrorism-response planner, paid in full by a grant, who starts work today developing a countywide terrorism-response plan.

"We have taken certain steps to ensure that we are doing everything possible to protect our community," said Lisa Bourcier, county spokeswoman.

Patrols picked up throughout the county to increase police visibility, Bourcier said, including at Myrtle Beach International Airport, where random vehicle checks and increased canine patrols provided added protection.

Tom Charlson, the airport's federal security director, said the security measures were mostly not noticeable.

"Some you can see, and some you can't see," Charlson said. "You will see more patrolling. We're asking the public, if they see anything of a suspicious nature or anything that looks funny, to report it to law enforcement or the TSA."

In Georgetown County, some sheriff's deputies were tasked with the specific duty of patrolling water and power facilities, the county's industrial plants and the Port of Georgetown, said Lt. T.L. Staub.

Progress Energy's nuclear plant in Brunswick County, N.C., increased its ever-tight security Monday when the terror threat moved to orange, said Mike McCracken, plant spokesman.

Access to the plant has been further restricted, patrols have picked up, and the perimeter around the plant is much larger than it was under the yellow threat level, McCracken said.

"There's definitely a higher state of alertness or awareness both for our security force and employees," he said.

Staff writer Kathleen Dayton contributed to this report.