Latest massacre pushes August US mass shooting deaths to a total of 35 At least 35 were killed in mass shootings in El Paso, Dayton and Odessa.

A Walmart in El Paso, a bar scene in Dayton, Ohio, and just hours ago, a chaotic scene on Texas roadways.

Those were the scenes of mass shootings in the United States, claiming at least 35 lives and injuring dozens others -- and all happened in the span of just one month.

On Saturday afternoon, on the last day of August, a gunman shot 25 people, killing four of them, during a shooting spree in Odessa, Texas, according to authorities. On Sunday, Sept. 1, authorities announced that 3 more people had died as a result of the shooting.

Authorities killed the suspect after he shot a police officer, hijacked a mail truck, and shot at “random people," police said. The identify of the suspect has not been released.

On Aug. 4, 22 people died and dozens more were injured at an El Paso, Texas, Walmart filled with weekend shoppers, including parents and children buying back-to-school items. The suspect was identified as Patrick Crusius, 21, of Allen, Texas.

Cruius, who authorities said was allegedly targeting Hispanics, is being charged with capital murder.

Less than 15 hours after the El Paso massacre, a mass shooting in Dayton, Ohio, took the lives of nine people and injured 27.

The suspect, 24-year-old Connor Betts, was shot dead by police at the scene. The entire mass shooting only lasted 32 seconds.

Before the shooting in Odessa, there were at least 18 mass shootings in the U.S. in 2019.

The FBI doesn't have an official definition of a mass shooting, but defines a mass killing as an incident in which three or more people, not including the suspect, are killed. Various groups and watchdog organizations keep their own lists, often using different criteria for what qualifies as a mass shooting.

In late July, three people were killed at a festival in California. Their victims' ages were 6, 13 and 25.

ABC News' Emily Shapiro and Meghan Keneally contributed to this report.