Drug overdose is the leading cause of accidental death in the United States. RTÉ News reports from Manchester, New Hampshire, second only to West Virginia for opioid deaths.

Last year, 64,000 people died from drug overdoses, according to official figures. That's up a fifth on 2015, and continues a rapid escalation seen in recent years.

It's also substantially more than the total military deaths suffered by US forces over the entire course of the Vietnam War (approx. 58,000 people over more than a decade).

It’s Friday afternoon in Manchester, New Hampshire and an emergency call comes in.

There's a possible overdose in the city library. Not behind the library, not a lane near the library, but in the library.

First responders say it’s a common occurrence in a city ravaged by drug abuse - mostly heroin and its more powerful, more lethal relation, the painkiller fentanyl.

September was the worst month on record with 112 overdoses and ten deaths in a city with a population of just 110,000.

Epidemic crosses generational divide

In areas where manufacturing jobs were concentrated, workers suffering from injury were prescribed pain-killers.

Some companies are accused of effectively pushing their drugs and encouraging GPs to over-prescribe, creating a population of addicts.

The US government eventually acted to tackle this practice, resulting in a drastic reduction in the amount of legal drugs being made available.

This coincided with a massive downturn in manufacturing. People were out of work and unable to access that medication.

High-powered heroin became available, laced with a potent additive fentanyl, synthesised in China and up to 100 times more powerful than heroin. The final product is then smuggled in through Mexico. It was a perfect storm.

Then there are the children of those addicted adults who started using drugs they found in bathroom cabinets.

The epidemic crossed the generational divide. Addicts can be teenagers or retired. No-one is immune.

Disrupting the supply chain

Nobody can put their finger on exactly why opioids have such a stranglehold on Manchester.

Police have clamped down on the supply chain, but many say the legal over-prescription of pain medication was partly to blame.

Police officer Anna Marie Martin has been working in Manchester, New Hampshire for 17 years. It's a long way from Ballybofey, Co Donegal, where she grew up. She paints a grim picture.

"It cuts across all borders; it cut across all clientele ... be you wealthy, college students, everybody had access to pills."

Speaking to RTÉ News, she said that people thought "'It's a pill - what can a pill do?' So people were becoming heroin addicts without really knowing it ... very quickly."

Danny Goonan was recently promoted to Chief of Manchester Fire Department. He says his responsibilities have changed radically from those of his predecessors.

He never thought the majority of his time would be taken up by dealing with a heroin epidemic.

For Fire Chief Goonan, who has been to the White House to discuss the matter, the real issue is fentanyl, because users have no idea what they are taking.

'A little pilot light'

Sylvie Redburn is in the early stages of recovery at the Serenity House facility.

She began heavy drinking as a teenager and became hooked on opioids when she was prescribed pain medication after an accident.

"The second you like the effect - you are doomed," she said.

In recent weeks, a young relative of hers nearly died from an overdose.

"I could see death in his eyes ... as long as you are breathing there is a little pilot light that continues to flicker."

That pilot light, thankfully, continues to shine, his life having been saved by an emergency medical team.

Politicians: Part of the problem?

This week, US President Donald Trump's pick for drug czar was forced to withdraw amid revelations that he spearheaded a bill that undercut the government's power to crack down on the opioid makers that were flooding the market with the addictive painkillers.

US Deputy Attorney General Rod Rosenstein has expressed concern, vowing that the US Justice Department would establish if the law had undermined the Drug Enforcement Administration's ability to do its job.

It's been more than two months since Mr Trump vowed to declare the opioid epidemic a national emergency.

He has yet to do so, fueling the chorus of criticism his administration is facing for its response to the crisis.

Mr Trump said he would make the declaration next week. Such a move would boost funding for various forms of treatment and give the government more flexibility in taking steps to expedite action.