ABC News September 1, 2019

Latest massacre pushes August US mass shooting deaths to a total of 35

WATCH: 5 deadliest mass shootings in recent US history

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

(MORE: 4 killed, 21 others injured in extended mass shooting in Odessa, Texas: Police)

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.

Dustin Fawcett via AP
In this image made from video provided by Dustin Fawcett, police officers guard on a street in Odessa, Texas, Saturday, Aug. 31, 2019.

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.

Mario Tama/Getty Images
A woman touches a cross at a makeshift memorial for victims outside Walmart, near the scene of a mass shooting which left at least 22 people dead, on Aug. 6, 2019 in El Paso, 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.

John Minchillo/AP
Authorities retrieve evidence markers at the scene of a mass shooting, Aug. 4, 2019, in Dayton, Ohio.

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

(MORE: At least 14 people have been arrested this month for threatening mass shootings)

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.