The Obama administration called attention on Monday to the nationwide surge in heroin abuse, with Attorney General Eric H. Holder Jr. saying a spike in overdoses from the deadly drug constitutes “an urgent and growing public health crisis.”

In a video message posted on the Justice Department’s Web site, Holder said the government is targeting violent traffickers who bring heroin into the United States while urging emergency personnel to carry an anti-overdose drug.

“Confronting this crisis will require a combination of enforcement and treatment. The Justice Department is committed to both,” said Holder, who noted that the Drug Enforcement Administration has opened more than 4,500 heroin-related investigations since 2011.

The message marked the first major public foray by the nation’s top law enforcement officer into a debate over heroin that has escalated since the recent death of actorPhilip Seymour Hoffman from heroin and other drugs. Heroin use rose 79 percent nationwide between 2007 and 2012, federal data show, and Holder said heroin-related deaths are up 400 percent in areas such as Cleveland.

In response, he said, the government is “doing more than ever to keep illicit drugs off the streets” through a DEA strategy aimed at reducing the supply of heroin “at all levels of the supply chain.” At the same time, Holder added, officials are partnering with police, doctors and others to increase prevention and treatment programs for heroin and prescription opioids such as OxyContin. Prescription drug abuse kills far more people each year than heroin, federal statistics show.

“It’s clear that opiate addiction is an urgent — and growing — public health crisis,” Holder said.

At times, the government has been slow to confront the problem. Gil Kerlikowske, who runs the Office of National Drug Control Policy as President Obama’s “drug czar,” recently said that he should have done more to raise awareness of heroin during much of the administration’s first term but that heroin is now a much bigger priority.

Top drug policy officials in the Obama and George W. Bush administrations have said that for a long time they rarely discussed repeated warnings from inside the government that the crackdown on prescription drug abuse could help fuel a new heroin epidemic. Many prescription drug abusers have switched to cheaper heroin, since prescription pills and heroin provide a comparable, euphoric high. Experts say the government’s actions in arresting doctors and shuttering “pill mills” contributed to the shift.

In the past few years, law enforcement has been aggressive in combating heroin. Federal data show that heroin trafficking cases rose 52 percent between 2008 and 2012. Federal officials say Mexican heroin production has increased, and traffickers are targeting areas of the United States hard hit by prescription drugs with a much cheaper product.

States are also increasingly confronting the spread of heroin use, usually by trying to prevent deaths. In recent years, 17 states and the District of Columbia have passed “good Samaritan” laws, offering some measure of immunity to those who seek medical help for an overdose victim.

Nearly 20 states and the District are also taking steps to allow more medical professionals to carry and administer naloxone, the drug Holder highlighted Monday, which reverses the effects of overdoses.

Even as his department has cracked down on heroin, Holder’s personal efforts to use the power of his office to raise awareness have been sporadic, a review of his speeches and public statements shows. The attorney general speaks often, in deeply personal terms, about how he witnessed the impact of drugs as a father and former prosecutor and D.C. Superior Court judge.

In 2009, soon after taking office, Holder said at a congressional hearing that he recognized heroin as an emerging problem.

In recent years, however, Holder’s drug-related efforts have focused on matters such as reducing mandatory minimum prison terms for some low-level, nonviolent drug offenders and crafting a federal approach to state laws legalizing marijuana.

Speaking at a 2012 congressional hearing focusing on prescription drugs, the attorney general cited a variety of illicit substances. “People, when they hear drugs, they think of crack. They think about cocaine, methamphetamine,” he said. He did not mention heroin.

John Carnevale, who worked for four drug czars in Republican and Democratic administrations, praised Holder’s remarks on Monday, especially his focus on public health and treatment along with enforcement. “What the attorney general is saying makes perfect sense,” Carnevale said.

But Theodore Cicero, an expert on addiction at Washington University in St. Louis, said the comments should have come much earlier. “Calling attention to heroin is a good thing, but there was a lot of dodging it for some time,” he said. “It’s too bad it took something likePhilip Seymour Hoffman to have the country wake up.”

A Justice Department official said Holder was reacting more to the broader national discussion about heroin than to the actor’s death and wanted to invoke that to highlight the department’s actions to combat it. “The attorney general wanted to have a voice in what has become a rising debate around the uptick in heroin-related deaths,” said the official, who spoke on the condition of anonymity to discuss internal deliberations.

Alice Crites and Reid Wilson contributed to this report.