A delusional man broke into a Waterville school while class was under way and screamed that someone armed with a gun was after him, trying to kill him.

A woman in Knox County tried to cut her teeth out with a knife because she thought they were embedded with ticks.

A Clinton woman took off her clothes, ran around, climbed into a drainage pipe and refused to come out.

People in the Howland area have reported seeing little green men or aliens and an Ellsworth-area woman thought she was a grizzly bear when police encountered her.

Those are just a few of the recent accounts of Mainers acting strangely while under the influence of the synthetic drug bath salts, which may have an innocent-sounding name but is a very dangerous — often psychosis-inducing — substance, according to police and medical professionals.

Bath salts first emerged earlier this year on the streets of Bangor, where it is called “monkey dust” and remains a daily problem. But it quickly has spread throughout the state. No county has escaped its reach.

“It’s just bad, bad, bad, and It’s everywhere,” Knox County Sheriff Donna Dennison said Friday. “It’s not just in Bangor or Portland. It’s everywhere, so everybody is concerned.”

Law enforcement and medical personnel in communities that have yet to see the drug arrive in full force — Houlton, Portland, Biddeford, Dover-Foxcroft and others — all say it’s just a matter of time before it worsens.

“Bath salts is quickly becoming an epidemic for law enforcement and something we are all starting to deal with,” Brunswick police Lt. Michael L. Moody said recently.

The drug can be snorted, smoked, injected or swallowed and is cheap, addictive and causes users to act unpredictably, Bangor Police Chief Ron Gastia said last week.

Bangor police respond to one to three calls a day involving the stimulant, which looks like cocaine but usually contains mephedrone or methylenedioxypyrovalerone, known as MDPV, he said. While the Queen City has big numbers, “we are not the drug capital of the world by any means,” Gastia said.

Penobscot County accounts for about 32 percent of the state’s 121 bath salts poisonings — overdoses — reported between January and Sept. 21, but there have been big jumps in Kennebec and Knox counties, according to data from the Northern New England Poison Control Center in Portland.

“It’s exploded down here,” Rockland police Sgt. Don Finnegan said recently.

Since mid-April, police and deputies in Knox County have responded to more than 143 incidents involving bath salts, 91 of them occurring in Rockland, the sergeant said.

“The thing that is common with bath salts users is severe delusion, paranoia — people are out to get them. People are chasing them,” Finnegan said.

Because the drug users truly fear for their lives, they pick up knives, guns and other weapons and are a danger to themselves, the people who love them and the law enforcement and medical personnel dispatched to help, the Rockland sergeant and others say.

“It’s a nightmare,” Finnegan said.

At least two men in Maine, one in Bangor and one in Rockland, attempted to commit suicide by cop while under the influence of bath salts, police in those communities have said.

Bath salts users encountered by law enforcement are typically in crisis, Gastia, Finnegan and Dover-Foxcroft police Officer David Wilson said.

“We don’t get involved until somebody has taken enough to flip out on it,” Wilson said.

“What we’re seeing is the adverse reaction,” Bangor’s police chief said. “That doesn’t mean that is the whole population [of bath salts users].”

“When we get called, it’s because people are on the extreme edge,” the Rockland sergeant said. “We’re just getting the fringe.” He said there are certainly many more users who go undetected.

Bath salts became illegal in Maine at the beginning of July, but those caught with the drug are issued a civil offense and dealers face only a misdemeanor charge.

Maine legislators, led by Gov. Paul LePage, are looking to stiffen bath salts penalties and the U.S. Drug Enforcement Administration and Congress are both working to make the main components of the hallucinogenic stimulant illegal.

The drug is banned in 31 states but is sold legally at convenience stores, head shops and online in the remaining unregulated states.

Hospital officials from The Aroostook Medical Center in Presque Isle to Maine Medical Center in Portland have seen agitated patients on bath salts acting erratically, with increased blood pressure, heart rates and body temperatures, hospital officials said.

“We haven’t tracked the number of cases we’ve seen in our emergency departments, but … the general feeling is that we’re seeing fewer cases of patients under the influence of bath salts since the law passed,” Dr. Guy Nuki, emergency room operations chief at MaineGeneral Medical Center’s Thayer Campus in Waterville, said last week.

“We have seen some but not a lot, but we know it’s an emerging issue,” Andy Soucier, spokesman for The Aroostook Medical Center, said of bath salts cases.

Most bath salts users have prior drug problems, Gastia and Dr. Doug Boyink, emergency department director at MaineGeneral’s Augusta Campus, said recently.

“These people also do not advertise their substance use, but have unusual toxic symptoms, and almost always have abused other substances,” Boyink said.

Poison center numbers show only one bath salts overdose in Maine during 2010. The county-by-county breakdown so far for 2011 show Penobscot County with the most bath salts poisonings, at 39, followed by Knox County with 20, or 16.7 percent, and Kennebec County with 18, or 15 percent.

Agents with the Maine Drug Enforcement Agency have seen the stimulant surface in areas close to Canada; near the New Hampshire border and in all areas in between.

After the drug took off in Knox County, “it kind of blossomed from there,” Ken Pike, MDEA’s Division I commander, who covers southern Maine, said Thursday. In April, “I started hearing about it in York County, in the southern part of the state, and at the border.”

Darrell Crandall, MDEA Division II commander, who covers from Kennebec and Somerset counties north, said his agents are finding bath salts in the Bangor area with pockets of new users in other areas.

“Aroostook County, particularly central Aroostook County, has recently seen a number of incidents,” he said, adding that Presque Isle is on the list.

The Lewiston MDEA field office supervisor, Matt Cashman, said his undercover agents are just beginning to see users of the drug and are “hearing more … from our street sources about bath salts being out there.”

He described the drug as “a tidal wave sweeping over the state” and said most law enforcement agencies, fire departments, emergency responders and hospitals that deal with despondent people have taken or are planning classes to educate their ranks about how to handle users of the drug.

Ellsworth police Chief John DeLeo and Waterville police Chief Joe Massey both said bath salts users remind them of drug addicts on PCP or LSD back in the 1970s and ’80s who often hallucinated about seeing monsters.

“It’s the bizarre behavior that we’re seeing again,” Massey said. “They don’t register danger and don’t recognize authority and sometimes don’t even acknowledge you.”

He used a Waterville man — recently found standing at the edge of the woods screaming nonsense at nearby trees — as an example of a bath salts user who didn’t even realize police were there.

Sometimes “there is just no talking to these people,” Massey said.

Synthetic bath salts are not regulated by the Food and Drug Administration because the drug is not marketed for human consumption, so users take a risk every time they consume the concoction of lab-made drugs.

“One person could take it and have a great time and the next person takes it and has a horror story,” DeLeo said.

The paranoia experienced by users sometimes lasts well beyond when the drug leaves their systems, Wilson said. “The flashbacks can last for days.”

Most law enforcement leaders stressed the need for a field test for bath salts to help officers identify the powder, which often is white but can also be yellow to brown. Investigators now have to send suspected bath salts samples to a lab in Augusta for testing at a cost of around $100, Crandall said.

Pike said he knew bath salts were going to be problem in Maine when the MDEA started getting calls in the spring from people concerned about their loved ones using the drugs.

“People were actually calling for help” before the drug was illegal, he said. “That’s a first. It’s pretty unusual to have someone’s wife, boyfriend or girlfriend asking agents to help them” with an emerging drug.

With all the unpredictable side effects and strange behavior of people all over the state, Crandall said, “it’s pretty hard to believe people are still using it.

“It doesn’t seem to make sense,” he said.

Those with questions about bath salts can contact their local law enforcement agency, the state’s Office of Substance Abuse at maine.gov/dhhs/osa or the poison center at 800-222-1222.