Authorities work at the scene of a mass shooting in Dayton, Ohio, on Sunday.

Nine people in Ohio have been killed in the second mass shooting in the US in less than 24 hours, and the suspected shooter is also deceased, police said.

Dayton police tweeted that an active shooter situation began in the Oregon District at 1:22am, 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.

Gunman kills 20 at Texas Walmart store in latest US mass shooting

The suspected shooter's identity has not been released.

Authorities work at the scene of a mass shooting in Dayton, Ohio, on Sunday.

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.

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.

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.