Nine people have died and another 27 were injured after a gunman opened fire in Dayton, Ohio, less than a day after 22 people were killed in a shooting in El Paso, Texas.
Dayton Police said the shooting suspect is also deceased. They identified him as a 24-year-old man.
Police said it wasn't close to establishing a motive for the shooting but that there was "no indication" of a racial motive.
The incident started shortly after 01:00 am local time (07:00 CEST) and officers who were in the "immediate vicinity" in the city's Oregon district "were able to respond and put an end to it quickly," police added.
The nine victims were all between the ages of 22 and 39, police confirmed at a press conference. One of the victims was the shooting suspect's sister.
On Monday, authorities said that at least 32 people were wounded during the shooting and that 14 of them are from gunshots. Eleven remain hospitalised.
Dayton's police chief said the shooting suspect may have had as many as 250 rounds of ammunition.
Dayton Mayor, Nan Whaley said she's "heartbroken" and thanked first responders, who neutralised the shooter in less than a minute, "for all that you've done."
She later told reporters that the suspect had been wearing body armour and that he had been carrying a .223 calibre high capacity magazine as well as "additional magazines." Police said he had two weapons, but one was left in the vehicle.
The shooter had travelled to the district with his sister and one other person, police said. The person who travelled with them was injured in the shooting.
"If Dayton police had not gotten to the shooter in under a minute — and think of the 26 injured, nine dead — hundreds of people in the Oregon district could be dead today," she stressed.
"As a mayor this is a day we all dread," she went on, deploring that Dayton was the theatre of "the 250th mass shooting in America" so far this year.
Deputy police Chief Matt Carper said that the initial investigation appeared to suggest only one shooter had been involved but added: "We are at the early stages so we can't confirm that this is the only person involved."
Greg Semon, from the local Miami Valley, said the facility had treated 16 patients of which 12 had been treated and released by 10:00 am local time. One remained in "critical condition".
Kettering Health Network spokeswoman Elizabeth Long added that nine patients at been treated at three of the group's facilities and that three remained in "serious conditions."
Police said the shooting took place on E 5th street in the centre of Dayton, Ohio. The suspect was killed by police outside Ned Peppers bar, in the heart of the district.
"All of our staff is safe and our hearts go out to everyone involved as we gather information," the bar said in a post on Instagram.
The Oregon district was to re-open in the early afternoon.
The shooting in Dayton comes just hours after 22 people were killed and 26 more injured in El Paso, Texas when a gunman opened fired in a Walmart and around a nearby shopping mall on Saturday.