St. Paul, MN (KROC-AM News) -- Officials say a recent spike in heroin overdose deaths speaks to a bigger problem across the state.

The Minnesota Bureau of Criminal Apprehension believes heroin circulating in the state, which may be laced with other narcotics, is responsible for at least 7 overdose deaths and over a dozen non-fatal overdoses over the past few weeks, mainly in north-central Minnesota.

Investigators are working to identify the source of the especially deadly heroin, but officials also stress that communities across Minnesota have seen increases in drug overdoses and law enforcement agencies have reported a significant jump in heroin seizures. The BCA says heroin seizures by Violent Crime Enforcement Teams in the state last year totaled 18 pounds, which is a 125-percent increase from 2011.

“These tragic heroin overdoses are unfortunately part of a larger statewide opioid drug abuse problem that often begins with inappropriate use of prescription opioid pain relievers” said Department of Health Commissioner Dr. Edward Ehlinger. "Prevention of addiction and inappropriate use of opioids requires a public health approach that includes looking at how we manage pain and community level factors that influence individual behaviors. The Guidelines for Prescribing Opioids for Chronic Pain announced by the CDC yesterday is a good example of an approach that can help us more effectively treat pain, promote health and reduce harms."

BCA officials say the Violent Crime Enforcement Teams also seized a record amount of methamphetamine and marijuana concentrates in 2015.