Dozens of law officers and emergency personnel sealed off Scotland Correctional Institute Tuesday after an unknown substance sickened employees there.

The substance is believed to be perfume, officials say.

At about 10:30 a.m., two employees working in the mail room of the prison developed a rash and hives on their neck and arms while checking envelopes and packages, according to a report by the Laurinburg Fire Department.

The two were sent to the hospital and the entire facility was put on lock down, the report said. There were 26 other employees working in the room and all were prevented from leaving for fear of possible infection.

About an hour later, prison officials contacted the Laurinburg Fire Department – the local hazardous material unit – to check for contaminants in the mailings that could have caused the outbreak.

Uncertain what might be at the scene, the local fire department called in the North Carolina Regional Response Team – based at the Fayetteville Fire Department – to check the mail room, officials said.

"We're not equipped to do a Level 1 hazmat," Laurinburg Engineer Chad Donaldson said.

"A report was received for the team out of Fayetteville to check a suspicious package," Fayetteville Fire Capt. Steve Drew said. "It turned out to be a letter laced with perfume."

Several hundred envelopes are being sent off for testing as a precaution.

Precautions were taken at the scene while the teams were investigating the incident, according to Donaldson. Air conditioning was cut off to prevent possible circulation of the agent and the prison was locked down.

He also said that no Laurinburg firefighter entered the mail room so they did not have to go through decontamination procedures.

The Scotland County Rescue Squad, Scotland County Health Department, State Department of Public Health and Human Services, State Bureau of Investigation, Federal Bureau of Investigation and U.S. Postal Inspectors Service also responded to Tuesday's incident.

Administrators at the prison were off for Veterans Day and could not be reached for comment.