Even before Dallas, Texas had more police officers killed in the last 18 months than any state Since 2015, gunfire deaths involving officers are up 75 percent in the U.S., data shows.

More police officers have died in the line of duty in Texas during the last 18 months than any other state, a number bolstered by the downtown Dallas ambush last week that left five officers dead.

At least 23 law enforcement officers in Texas, including 11 this year, have died in Texas since Jan. 1, 2015, according to data compiled by the Officers Down Memorial Page, which tracks officer fatalities in real time. Before the Dallas ambush July 7, Texas had the most officer fatalities with six in 2016.

In 2015, Texas also had more officers killed in the line of duty than any other state with 12 fatalities.

Those deaths stemmed from eight incidents involving gunfire, six of which happened this year, including the five in Dallas. Most of the other deaths involved a vehicle.

RELATED: Obama pays tribute to Dallas officers shot in racial attack

Since the July 7 ambush in Dallas, four officers across the country have died — including one in Texas — bringing the year's total halfway through 2016 to 62 fatalities in the U.S.

Four officers died in Louisiana, which has been riddled with protests since the death of Alton Sterling, making it the second-deadliest state in the country for police officers.

The gallery above features images of officers who died in the line of duty since last August in Texas.

Fatalities include employees from local police department, sheriff's offices and state police.

Last year, Texas saw 12 officer fatalities, making up nine percent of the total 130 deaths across the country.

The Lone Star State was followed by New York, which had 11 officer fatalities. And since 2015, gunfire deaths involving officers are up 75 percent in the U.S., data shows.

RELATED: San Antonio police officers honor slain Harris County deputy Darren Goforth in somber ceremony

In 2014, 26 officers died in the line of duty in New York, the most of any state that year, followed by California and Texas, which had 16 and 11 deaths, respectively. Sixteen of the deaths of New York officers in 2014 were associated with injuries sustained during the Sept. 11, 2001 attacks.

The violence and threats toward police has continued since the Dallas ambush, reports show, even though, according to the Washington Post, the average number of police intentionally killed each year under Obama is 62 annually through 2015, the lowest its ever been.

Under President George W. Bush, the average was 72, and 81 deaths before that under President Bill Clinton.

On Tuesday, the same day President Barack Obama visited Dallas to speak at the police memorial honoring the five who lost their lives trying to stop shooter Micah Johnson, Austin Police Chief Art Acevedo declared a staffing emergency, enabling the department to force officers to work overtime for the next two weeks, after a threat to kill officers on 6th Street was made on social media.

"We know there is evil in this world," Obama said Tuesday. "That's why we need police departments."

Two days after Johnson, 25, killed five police officers, the Dallas Police Department received a threat against law enforcement across the city. That same day, a Bexar County Sheriff's Office spokesperson was followed to her car, a brick was thrown at a BCSO Tahoe and shots were fired at the San Antonio Police Department headquarters in three separate incidents.

Outside of Texas on Saturday, two people made threats to police officers via social media.

A Wisconsin man was arrested after he allegedly posted calls on social media for black men to kill white police officers. And in Waveland, Mississippi, police received threats via phone and social media involving possible gunfire attacks Saturday night and Sunday.

RELATED: Manifesto found at the home of Dallas gunman

One day after the Dallas attack, the Fayetteville Police in North Carolina said they received more than 60 threats during a 6-hour period and a Connecticut man was arrested for allegedly telling a gas station clerk he wanted to "snipe" police officers.

Additionally, a Chicago woman was arrested at her home after she allegedly posted a threat to Facebook to shoot any police officer who pulls her over and asks her to get out of her car.

A Louisiana man was jailed Friday after he allegedly posted a video to social media showing a police unit in front of him at a fast-food drive thru where he says he wants to shoot and kill an officer.

MORE: Two bailiffs were shot dead in Michigan.

Detroit police arrested four men who allegedly made threatening Facebook posts toward officers.

Three were arrested in North Carolina after police said they ran into the Bryson City Police Department yelling "let's kill us a cop."

The Associated Press contributed to this report.

kbradshaw@express-news.net

Twitter: @kbrad5