Minnesota federal authorities say criminals are continuing to find innovative ways to steal painkillers and other opiates.

In the past year, for example, charges have been brought against a paramedic who siphoned liquid morphine intended for ambulance patients and a 50-year-old woman who used identity theft to steal nearly 70,000 painkillers.

A doctor from Pelican Rapids joined the ranks on Wednesday. Blair A. Nelson, 43, pleaded guilty to obtaining hydrocodone, oxycodone and other prescription drugs by writing and filling fraudulent prescriptions. Authorities said he filled prescriptions for 1,700 pills, and continued even after his license was suspended in 2013.

The prevalence of prescription opioid-related crime and abuse will bring several hundred experts in public health and law enforcement to the University of Minnesota next month for the first statewide conference to define the scope of the problem and develop a solution. Keynote speakers will include Gov. Mark Dayton and Sen. Amy Klobuchar, D-Minn.

"Prescription drug diversion is an ongoing threat to both public safety and public health," said U.S. Attorney Andrew Luger. "Working closely with colleagues at the Drug Enforcement Administration and in local law enforcement, we are clamping down on prescription drug fraud and abuse."

Pain pill crimes are more frequently charged in state court, where defendants have a greater opportunity to enter diversion programs or drug court. Sentences are generally far longer in the federal system.

The drug conference, which will be held Aug. 25, is sponsored by organizations ranging from Hazelden Betty Ford Foundation to the Mayo Clinic.

In 2013, the state Health Department reported 507 Minnesotans died of all types of drug overdoses including 329 in the 11-county metro area. Deaths from prescription pain relievers and heroin, a cheaper substitute in the opioid family, accounted for many of them. By comparison, 374 Minnesotans died in motor vehicle accidents.

Heroin deaths have increased sharply in many states, according to the U.S. Centers for Disease Control, but nearly twice as many people died from prescription drug overdoses as from heroin. In Minnesota, 200 people died from overdosing on prescribed pain relievers in 2013; 91 died from overdosing on heroin.

Pain pill prosecutions

Since late October, the U.S. attorney's office in Minneapolis has prosecuted at least five significant opioid cases. Anissa Shores, 37, employed at a pharmacy in Burnsville, pleaded guilty to stealing 67,000 doses of hydrocodone, oxycodone, carisprodol and diazepam for personal use since 2011. She falsified the pharmacy's computer records, making it appear the pharmacy received smaller quantities than it actually received.

"She abused her position as a trusted member of the medical community," said Dan Moren, assistant special agent in charge of the local Drug Enforcement Agency.

In April, Nanci Dusso could receive up to a nine-year sentence for using false names, birth dates and Social Security numbers to get prescription drugs from clinics throughout Minnesota and Wisconsin. A tip from a suspicious nurse practitioner at a Mayo Clinic satellite location led to a multiagency investigation.

Three months later, paramedic Matthew Peterson, 39, was placed on probation for stealing liquid morphine from patients. He replaced the drug with saline solution, leaving more than 100 patients at greater risk for infection and pain. He was eventually caught trying to steal opioids from a Bloomington fire station, said John Redmond, special agent in charge of the Food and Drug Administration's office of criminal investigations in Chicago.

Omar Beasley was in charge of the most significant source of heroin and painkillers to Red Lake and White Earth Indian reservations and the surrounding communities.

"Drug dealers have no borders to follow and law enforcement has proved that they will cross all borders to get the job done as well," said William Brunelle, Red Lake's public safety director.

According to Nelson's guilty plea Wednesday and documents filed in court, he starting writing prescriptions in May 2013 to various pharmacies in Minnesota. He wrote the prescriptions in the names of family members and friends, then picked up the drugs for his own use.

"I'm proud of my client and all the hard work he's done [after he was charged]," said Thomas Plunkett, Nelson's attorney.

Plunkett declined to comment further because Nelson hasn't been sentenced yet. His sentence could range from probation to six months in jail and up to a $10,000 fine.