THOMASTON – The Thomaston post office was evacuated, cordoned off and closed Saturday after a worker discovered a white, powdery substance in two parcel post sacks that police say originated in Springfield, Mass.

It was one of at least five suspicious letters or packages found around the state and reported to the Maine Emergency Management Agency on Saturday. All proved harmless.

Wearing special suits, five members of the Rockland Fire Department Hazardous Materials Team quickly gathered up the packages at the Thomaston post office, sealed them in plastic hazmat bags and turned them over to Thomaston police and fire departments.

The materials were taken to the Department of Human Services’ health lab in Augusta for testing. A MEMA official late Saturday said the white powdery material tested negative for any harmful ingredients.

Darla Chafin, a MEMA planner, said she was pleased everyone is paying close attention to the FBI’s advisory about suspicious letters and packages. “I think everybody is being extra careful and maybe someone is having a little fun with us,” Chafin said.

Public safety officials are on high alert because at least 12 people nationwide have tested positive for exposure to anthrax since the Sept. 11 terrorist attacks. One person died – the first death in the United States related to anthrax in 25 years.

Chafin said most people would rather be safe than sorry. For example, one of Saturday’s reports came from Augusta, where a mother noticed white powder on her cupboard near a pile of mail. Although her husband had mixed baby formula on the counter, the mother wanted to be sure. So she contacted authorities who checked her mailbox and found no powder, Chafin said.

MEMA also received reports about an envelope in Winterport and a letter in Presque Isle. In both instances, the packages tested negative for a hazardous substance.

In Portland, postal workers were quarantined for the second day in a row Saturday after an envelope ripped open and a white powder scattered in the mailroom at the main post office there.

The post office was evacuated and shut down after the incident was reported shortly before 4 p.m. Eleven people were quarantined inside the building, and the powder was sent to Augusta, where it also tested negative as a hazardous substance.

The incident came one day after another envelope ripped open and scattered a white powder at the Portland post office, prompting officials to evacuate the building and quarantine people. That substance was determined to be starch.

Thomaston postal workers followed federal advisories in dealing with Saturday’s incident there, according to information provided by local police and fire officials.

Thomaston police Sgt. Kevin Haj said none of the six workers had direct contact with the white powder. He said a female postal worker discovered the white powder in two of the bags. He said there were three bags on a mail cart. The two bags had the powdery substance in them. A third sack, which came from Portland, was not opened, he said.

Adam Miceli, Rockland’s assistant fire chief, said postal workers contacted Penobscot Bay Medical Center in Rockport and the FBI.

“She never came in direct contact with anything,” Miceli said. “She just saw the stuff and called.” He said the postal worker went through a personal decontamination herself by washing with soap and water.

Later, Haj said, postal employees were not tested and basically “refused treatment.”

“I’m fine,” the female postal worker said during a telephone interview Saturday. The woman, who asked not to be identified, said the post office was closed before it was to reopen to the public. “It was scary. We should be wearing rubber gloves,” she said.

Haj did not know when the post office would reopen, but fire chief Bill Adams said Saturday the facility would open as soon as the test results were known. Since the test results were made available later Saturday night, the facility likely will open on schedule today.

Jack Krueger, director of the state Health and Environmental Testing Laboratory in Augusta, said all of the substances being found are being tested and retested.

Krueger said microbiologists look at the substances under a microscope, searching for any spores of the anthrax bacteria. Even if the preliminary test proves negative, the substances are placed overnight in a nutrient-rich broth to see if anything grows, he said.

“The spores are very, very small and it’s possible to miss them,” Krueger said. “That’s why in some cases there have been negative tests and then positive tests.”

Dr. Kathleen Gensheimer, the state epidemiologist, said people are right to be wary, but she also urged calm.

“Everyone across the nation is concerned about this potential threat, and the latest cases heighten those fears,” Gensheimer said. “But if fear is driving people to become … not logical in their thinking, the terrorists are succeeding.”

The Associated Press contributed to this report.