AUSTIN, Texas — Texas officials are investigating an "outbreak" of opioid overdoses in Austin after emergency personnel responded to dozens of incidents from Monday to Wednesday, resulting in the suspected deaths of nine people.

Austin-Travis County Emergency Medical Services responded to a total of 75 overdose cases from Monday to Wednesday evening, EMS Division Chief Angela Carr said at a news conference Wednesday. The Travis County medical examiner's office confirmed it is investigating nine cases as suspected overdose deaths, according to county spokesperson Hector Nieto.

Preliminary toxicology reports indicated the presence of fentanyl in nine cases, cocaine in eight and methamphetamine in three, Nieto told the American-Statesman, part of the USA TODAY Network. City officials initially convened Tuesday to provide information about the investigation of the suspected overdoses.

In what officials termed as the city's deadliest overdose outbreak in nearly a decade, Austin-Travis County Emergency Medical Services Assistant Chief Steve White said emergency responders received more than 50 overdose-related calls by Tuesday morning — an about 1,000% increase in overdose emergency calls in a day.

During a news conference Tuesday, White said Austin had not experienced the high volume of overdoses since 2015, when K2, a synthetic cannabinoid, struck the city. Austin-Travis County Emergency Medical Services typically receives one to two overdose calls per day, according to White.

According to the most recent data from the National Institute on Drug Abuse, more than 106,000 people across the United States died from a drug overdose in 2021. And deaths involving synthetic opioids — not including methadone — increased in 2021 with 70,601 overdose deaths.

"Over the past two decades, the United States has experienced a growing crisis of substance abuse and addiction that is illustrated most starkly by the rise in deaths from drug overdoses," the State Health Access Data Assistance Center said. "Since 2000, the annual number of overdose deaths from any kind of drug in the U.S. has multiplied nearly six times over, rising from 17,500 to over 106,000 people in 2021."

Fentanyl kills thousands of Americans.Could plugging a gap in U.S. intelligence save lives?

Overdose cases in Austin slowed down through the week

Overdoses have slowed since the beginning of the week. At the news conference Wednesday, Carr said emergency personnel had responded to seven overdoses Wednesday, compared with 37 on Monday and 27 on Tuesday, evidence that overdoses were decreasing day by day.

Prior to this week's rapid uptick in cases, EMS Capt. Christa Stedman said the agency had seen overdose "numbers trend at least a little bit downwards." Stedman emphasized that opiate use disorder and overdoses do not discriminate, affecting every race, age and socioeconomic stratum.

Authorities previously said overdose emergency calls began in downtown Austin at 1 a.m. Monday and spread to other parts of the city until 4 a.m. Tuesday. Many patients were found in cardiac arrest, White said Tuesday. 

Patients came from a range of ages and demographics, but none were under the age of 18, according to Austin Police Assistant Chief Eric Fitzgerald. Most calls were also concentrated in downtown Austin and came from businesses, residences, and public areas.

"There were patients that were unhoused; there were patients that were housed," White said. "There were patients that were at their workplace, and there were patients that were out in public spaces as well. It was not limited to one geographic location."

During the investigation, the medical examiner found an overdose that had occurred at 9 p.m. Sunday was overlooked and was not added to the cluster of deaths until later, according to Nieto.

On Wednesday, Stedman said many patients were not trying to take an opiate. Patients had been using K2, crack cocaine, Xanax, and a number of other substances.

She credited paramedics and community partners' efforts to "flood" the city with Narcan — an opioid-overdose antidote — as instrumental in saving many lives this week. Carr said more than 400 Narcan kits had been distributed by Wednesday afternoon.

"We have seen a number of cases where Narcan has been administered by civilians before we get there, and either the person is awake and is recovering, or they're well on their way to recovering," Stedman said. "We've actually seen a couple of cases where they've recovered fully and walked away before we got there."

Austin police identify 2 persons of interest

The Austin Police Department declined to provide additional updates into the investigation, citing a need to ensure the investigation's integrity, though it said it has identified two persons of interest. 

On Tuesday, Austin police Lt. Patrick Eastlick said the department had detained these two individuals in downtown Austin on Monday, charging one with a firearm possession felony. He said more charges were pending. The police investigation is being aided by the Drug Enforcement Administration and the Assistant U.S. Attorney's Office.

People found responsible for distributing fentanyl could face charges of murder or of manufacture or delivery of a controlled substance causing death or serious bodily injury, Eastlick previously said.

A new Texas law instituted tiered felony charges for producing, delivering, or distributing fentanyl in an effort to combat the crisis. The law allows for murder charges to be levied on guilty parties, with a maximum sentence of life imprisonment.

In a joint statement with Texas Against Fentanyl, the Williamson County Sheriff's Office told its residents "to remain vigilant and aware of the dangers posed by fentanyl."

The statement urged residents "to engage in open and honest conversations with family members, particularly teenagers, about the risks associated with fentanyl and other dangerous drugs. Heightened awareness and education are critical in preventing further harm and loss of life."

U.S. opioid epidemic

A RAND study published in February found that more than 40% of Americans know someone who has died of a drug overdose. RAND reported that more than 109,000 people in the country died from drug overdoses in 2022 and more than 1.1 million have died since 2000.

According to the State Health Access Data Assistance Center, a majority of drug overdose deaths involve opioids, including heroin and prescription painkillers. But in recent years, synthetic opioids such as fentanyl have become more widespread in drug overdose cases.

Fentanyl can be up to 50 times stronger than heroin and 100 times stronger than morphine, the Centers for Disease Control and Prevention said. Recent cases of fentanyl-related overdose are typically tied to illegally made fentanyl.

"It is a major contributor to fatal and nonfatal overdoses in the U.S.," according to the CDC. "Over 150 people die every day from overdoses related to synthetic opioids like fentanyl."

The U.S. Drug Enforcement Agency reported that more than 17.9 million fentanyl pills have been seized already in 2024. In 2023, the agency seized more than 78.4 million fentanyl-laced pills and nearly 12,000 pounds of fentanyl powder, which represent more than 376.7 million lethal doses of fentanyl.

Contributing: Phaedra Trethan, USA TODAY