RIO BRAVO, TX  (CBSDFW.COM/CNN) — An immigrant who was in the country illegally was shot and killed Wednesday by a Border Patrol agent in Rio Bravo, Texas, according to US Customs and Border Protection.

The agent was responding to a report of illegal activity near a culvert and discovered a group of immigrants who were in the country illegally, the agency said.

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The agent tried to apprehend the group, but he came under attack by people using blunt objects.

According to the Laredo Morning Times, agents were trying to halt an alleged human smuggling attempt. “The agent fired at least one round from his service-issued firearm, fatally wounding one of the assailants,” officials said in a statement.

The names of the agent and the deceased have not been released, but a bystander video posted on Facebook said the latter was a woman.

In the video, a woman yells at an agent: “Why are you mistreating them? Why are you mistreating them? Why did you (shoot) at the girl? You killed her. He killed the girl. She’s laying there and she’s dead.”

The video also showed an agent leading away some men. CBP said responding agents apprehended three undocumented immigrants.

The FBI and Texas Rangers are investigating.

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Rio Bravo is on the border with Mexico, about 170 miles south of San Antonio.

Immigrants’ clashes with Border Patrol

Wednesday’s incident comes as lawmakers continue to say that Border Patrol agents face rising dangers on the job and more than a month after President Donald Trump ordered the deployment of National Guard troops to secure the U.S. Mexico border.

But Border Patrol agents lead far safer work lives on average than most other law enforcement officers. Data show that assaults against the 19,500 agents of the Border Patrol have been dropping, not rising.

After surging sharply in fiscal year 2017, according to CBP figures, assaults against agents have fallen 32% through the end of March, compared with last year.

Border Patrol agents have reported being assaulted at less than half the rate of other law enforcement officers.

In fiscal 2016, the most recent year for which figures are available, the nearly 600,000 law enforcement officers whose agencies reported assaults and deaths to the FBI suffered one assault per 10 officers, compared with one assault for every 44 Border Patrol agents.

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