Dayton police tweeted that an active shooter situation began in the Oregon District at 1 a.m., but that officers nearby were able to "put an end to it quickly." At least 16 others were taken to local hospitals with injuries, police said.

The suspected shooter's identity has not been released.

Miami Valley Hospital spokeswoman Terrea Little said 16 victims have been received at the hospital, but she couldn't confirm their conditions. Kettering Health Network spokeswoman Elizabeth Long said multiple victims from a shooting had been brought to system hospitals, but didn't have details on how many.

With a population of around 140,000 Dayton is in western Ohio, around 55 miles (90 kilometers) northeast of Cincinnati, 75 miles (120 kilometers) west of Columbus and 120 miles (195 kilometers) east of Indianapolis. The Oregon District is a historic neighborhood near downtown Dayton that's home to entertainment options, including bars, restaurants and theaters. Police have not said where in the district the shooting took place.

The FBI is assisting with the investigation. A family assistance center will be set up at the Dayton Convention Center.

The Ohio shooting came hours after a young man opened fire in a crowded El Paso, Texas, shopping area, leaving 20 dead and more than two dozen injured. Just days before, on July 28, a 19-year-old shot and killed three people, including two children, at the Gilroy Garlic Festival in Northern California.

The El Paso shooting was the 21st mass killing in the United States in 2019, according to the AP/USATODAY/Northeastern University mass murder database that tracks all U.S. homicides since 2006 involving four or more people killed — not including the offender — over a short period of time regardless of weapon, location, victim-offender relationship or motive. That makes Sunday's shooting in Dayton the 22nd mass killed in the U.S. this year.

The first 20 mass killings in the U.S. in 2019 claimed 96 lives.