Israeli Prime Minister Benjamin Netanyahu also addressed the attacks at the opening of the weekly cabinet meeting held Sunday in Eilat.

"In the past 24 hours, we have witnessed two murderous attacks in Texas and Ohio. On behalf of all government ministers and all citizens of Israel, I send condolences to the bereaved families, best wishes for recovery to the injured and solidarity with the mourning of the American people,” he said.

Police officers who were on routine patrol nearby arrived on the scene in less than a minute and shot the attacker dead, likely preventing a much higher casualty toll, police and the city's mayor said.

Assistant Police Chief Matt Carper told reporters the incident began at 1 a.m. local time in Dayton's Oregon District, a downtown historic neighborhood popular for its nightclubs, restaurants art galleries and shops.

The motive behind the shooting was not immediately clear, and investigators believe the individual had acted alone, Carper said. The authorities did not disclose the shooter's identity.

A total of 10 people were killed, including the assailant. Twenty-six others were injured and taken to hospitals across the area, Mayor Nan Whaley told reporters, though the extent of their injuries was not known.

She said the suspect was wearing body armor and was armed with a rifle firing .223-caliber rounds with high-capacity ammunition magazines.

Had police officers not confronted the suspect as quickly as they did, "hundreds of people in the Oregon District could be dead today," the mayor said.

Democratic Speaker of the House, Nancy Pelosi, tweeted her condolences on Sunday. "In less than 24 hours, another American community has been devastated by the tragedy of gun violence, this time in Dayton, Ohio. The hearts of all Americans break for the families & friends of those injured & murdered in this act of terror. #EnoughIsEnough" In less than 24 hours, another American community has been devastated by the tragedy of gun violence, this time in Dayton, Ohio. The hearts of all Americans break for the families & friends of those injured & murdered in this act of terror. #EnoughIsEnough August 4, 2019 FBI agents were assisting in the investigation.Democratic Speaker of the House, Nancy Pelosi, tweeted her condolences on Sunday. "In less than 24 hours, another American community has been devastated by the tragedy of gun violence, this time in Dayton, Ohio. The hearts of all Americans break for the families & friends of those injured & murdered in this act of terror. #EnoughIsEnough"

Sen. Sherrod Brown of Ohio also reacted.

“As Ohio wakes up this morning to the news of this horrific attack, Connie and I are filled with sadness for the victims and their families and gratitude for the police officers who responded to the scene and the medical professionals caring for the injured,” Brown tweeted.

Added the senator: “We are also angry — angry that shooting after shooting politicians in Washington and Columbus refuse to pass sensible gun-safety laws to protect our communities. We are still learning about the attack in Dayton and we don’t know exactly what, if anything, could have prevented...”

“We are still learning about the attack in Dayton and we don’t know exactly what, if anything, could have prevented this specific tragedy,” Brown said further in a statement early Sunday from his office. “But we know thoughts and prayers are not enough, we have a responsibility to act.

“My office stands ready to assist the Dayton community with whatever is needed to investigate and recover from this attack.”

“Our hearts are heavy this Sunday morning as our family joins all Ohioans to mourn the loss of innocent lives from the senseless tragedy in Dayton,” Ohio House Speaker Larry Householder said. “The innocent victims & their families are in our prayers. We commend first responders whose bravery & faithful courage saved lives.”

The shooting in Dayton, a riverfront city of about 140,000 people in southwestern Ohio, came just 13 hours after a mass shooting at a Walmart store in El Paso, Texas, where 20 people were killed and 26 others wounded. The 21-year-old suspect in that shooting was arrested.

The Ohio shooting was the third major outbreak of U.S. gun violence, coming seven days after a teenager killed three people with an assault rifle at a food festival in Northern California before taking his own life.

Pope Francis condemned the attacks on "defenseless people" in the U.S. shootings in his Sunday message and blessing from St. Peter's Square.

The Dayton Daily News said the latest shooting occurred at or near a tavern called Ned Peppers Bar.

The newspaper cited a Facebook post from James Wilson, who said he was a customer sitting on a patio just outside the bar when the shooting occurred in front of the establishment.

"He (a gunman) tried to get into the bar but did not make it through the door," Wilson wrote. "Someone took the gun from him and he got shot and is dead."

Deb Decker, a spokeswoman for emergency services in Montgomery County, Ohio, told CNN the assailant had been making his way to Ned Peppers from another bar when someone grabbed the barrel of his rifle, and he drew a handgun, but was then shot as police arrived.

Dayton Daily News/TNS contributed to this report. The mayor said the carnage in Dayton marked the 250th mass shooting in the United States so far this year, a figure that could not immediately be verified.Dayton Daily News/TNS contributed to this report.

US President Donald Trump condemned the shooting, which left 10 people dead in Dayton, Ohio, on Sunday."The FBI, local and state law enforcement are working together in El Paso and in Dayton, Ohio. Information is rapidly being accumulated in Dayton. Much has already be learned in El Paso. Law enforcement was very rapid in both instances," Trump tweeted.The shooting took place early Sunday, when a gunman dressed in body armor opened fire in a downtown district of Dayton, Ohio killing nine people and wounding at least 26 others, authorities said, in the second deadly mass shooting in the United States in less than a day.“Fran and I are absolutely heartbroken over the horrible attack that occurred this morning in Dayton,” Ohio Gov. Mike DeWine tweeted. “We join those across Ohio and this country in offering our prayers to victims and their families.”