A drug overdose-rescue kit from a training session on how to administer naloxone, an opioid-overdose antidote. (Carolyn Thompson/AP)

Four people are said to have overdosed on opioids — two fatally — over the holiday weekend in Alexandria, prompting city officials to warn on Monday about the dangers posed by the illegal use of narcotics.

The overdoses occurred within a 72-hour period in different parts of the city, said Capt. Gregg Ladislaw of the Alexandria Police Department’s criminal investigations division.

One of the people who fatally overdosed was a 50-year-old woman who died in the west end of Alexandria; the other was an Alexandria resident who was brought to a hospital but could not be revived, he said.

The two who survived — a 27-year-old woman and a 28-year-old man — were treated with naloxone, an opioid-overdose antidote, by first responders, Ladislaw said. One of them had overdosed in a grocery store bathroom on the west end, he said.

None of the victims’ names were released.

Last year, the city saw 49 nonfatal and eight fatal opioid overdoses, about the same as in 2017, when there were 50 nonfatal and nine fatal overdoses, said Liz Wixson, director of clinical and emergency services at the city’s Department of Community and Human Services.

Alexandria, which is just south of the District, has about 160,000 residents.

“To have four in a three-day period, when we usually only have about 50 to 60 total in a year, is enough to raise our concern that it may possibly be a concentrated batch of narcotics, maybe mixed with something,” Ladislaw said. “We won’t know that until we get the tests back.”

Wixson said the city has seen three or four such spikes in past years; one of those surges stemmed from drugs that had been mixed with fentanyl, a strong synthetic opioid, Ladislaw said.

Alexandria Mayor Justin Wilson (D) said the city has increased resources to treat drug addiction over the past two years and is trying to get the word out to people who need help.

“This is not a new situation for us, unfortunately,” Wilson said.

The opioid epidemic has been seen as a rising crisis in the region and nationwide. Federal officials, as well as state officials in Virginia and Maryland, among others, have declared opioid addiction a public health emergency, with officials pointing to heroin cut with strong synthetic opioids such as fentanyl to be particularly deadly.

D.C. officials have struggled to develop programs to successfully address a tripling of overdose deaths in recent years, but city officials last month launched a plan to halve the number of fatalities over the next 20 months.

Wixson said Alexandria has moved to create an intervention program for people addicted to opioids, with police encouraging treatment options — including giving out burner cellphones programmed with the phone number of a treatment center. Wixson said a quarter of the people who receive the phones end up entering treatment.

“It’s been a really tragic few days in Alexandria, not only for these four people, but for their families and the people who love them,” she said. “In the face of the opioid crisis and in particular these four tragedies, it’s really important for people to know there is hope. We know the treatment works.”