A sharp rise in US deaths from heroin and prescription abuse has created an "urgent public health crisis," Attorney General Eric Holder declared Monday, promising tougher enforcement and improved drug treatment.

In a statement on the Department of Justice website, Holder said deaths from overdosing on heroin had risen by 45 percent between 2006 and 2010.

"Right now, few substances are more lethal than prescription opiates and heroin," Holder said.

"The cycle of heroin abuse commonly begins with prescription opiate abuse," Holder said, calling rise in use of the illegal opiate "a sad but not unpredictable symptom of the significant increase in prescription drug abuse we've seen over the past decade."

Holder urged firefighters and ambulance workers to carry the overdose-reversal drug naloxone, which can restore breathing to the victim of a heroine or opioid overdose.

He also is encouraging US law enforcement agencies to train and equip their personnel about how to administer the drug.

The Justice Department said 17 US states, as well as the city of Washington, DC, have amended their laws to increase access to the drug, reversing more than 10,000 overdoses since 2001.

Holder also pledged more robust law enforcement to fight against "practitioners that illegally dispense prescriptions, pharmacists that fill those prescriptions, and distributors that send controlled substances downstream without due diligence efforts," the top US prosecutor said.

"Confronting this crisis will require a combination of enforcement and treatment. The Justice Department is committed to both."

The epidemic of heroin use in the United States came into an international spotlight last month after the death of Oscar-winning actor Philip Seymour Hoffman.

Hoffman, 46, died in his New York apartment on February 2 after taking a cocktail of drugs that included heroin, an autopsy report said.

More than 50 sachets of the illegal opiate were found in Hoffman's apartment at the time of his death, and he was known to have past problems with drug addiction.