A police chief has posted a direct Facebook message to an alleged drug dealer, linked with a overdose death, that she can run but she cannot hide. Allegheny County boss Chad King warned the suspected opioid fugitive: "We will find you."

Latoya "Toy" Marie Rosiek is wanted on suspicion of supplying fentanyl – an opioid-like heroin but 50 times stronger – to a person who later died of an overdose in Bridgeville, Pennsylvania.

King alleges that the mother, 32, went underground after police linked her to the death. Now he has a warrant for her arrest as well as thousands of Facebook followers with whom to share her picture.

"I am asking for the public's assistance in helping us locate this fugitive! Let's show her what a powerful tool social media can be!" he wrote in the post, before explaining ways people could contact his team confidentially.

He addressed Rosiek directly, saying: "I have known you since you were a teenager living in Bridgeville. Let's end the foolishness, do the right thing and turn yourself in. You will be treated fairly.

"Here's what you are up against... this post will more than likely reach well over 100,000 people within the next 24 hours, or less. This department has a success rate of 100% when utilising social media to locate and apprehend wanted felons.

"The odds are not in your favour. In fact, there is no doubt in my mind that you will be reading this post within the next few hours. Your chest will begin to tighten, your heart will begin to pound, you may start trembling and break into a sweat as you are overcome with feelings of nausea.

"You will soon realise that people you once trusted are now diming you out. It's not worth the stress on you, your family, or your children to continue running and looking over your shoulder. I will tell you the same as I have told others... WE WILL FIND YOU."

Fentanyl and the US opioid epidemic

A staggering 64,000 people died of drug overdoses in the US in 2015 – a more than four-fold increase on 20 years previously. The increased prevalence of fentanyl-laced heroin is at the heart of the US opioid epidemic.

Fentanyl is a painkiller prescribed for some cancer sufferers. However, the fentanyl making its way onto the black market is typically imported from China by drug dealers who use it to dilute heroin in a bid to boost profits.

But the demand for heroin was in part created by the overly-liberal prescription of medicinal opioids, such as Oxycontin, by US doctors in the 90s. Some 75% of heroin users started with painkillers, according to a study in JAMA psychiatry.

The impact of an under-regulated health sector was laid bare by research produced in 2015 in the Annual Review of Public Health. It showed, without any doubt, the correlation between legal opioid sales/prescriptions in the US and the rate of opioid deaths.

Opioid sales deaths US
Opioid deaths correlate strongly with opioid prescriptions Annual Review of Public Health