NEW ORLEANS, Louisiana (CNN) -- A man who was stopped for questioning beat and wrestled a gun away from a New Orleans police officer and shot her to death, authorities said.
Officer Nicola Cotton, 24, was shot to death by a man who fit the description of a rape suspect.
The incident was the latest crime to shake New Orleans, a city that has suffered a spike in murders since Hurricane Katrina in 2005.
About 10 a.m. Tuesday, Officer Nicola Cotton, 24, was alone in a car patrolling the city.
She spotted Bernel Johnson, a 44-year-old who fit the description of a suspect in a recent sexual assault. She approached him and began to question him.
When she tried to handcuff him, Johnson -- twice the officer's size -- overpowered her and grabbed her baton and began to beat her for several minutes in the head and arms, said a New Orleans Police spokesman.
Johnson then tore the officer's gun from its holster and allegedly shot her once in the head and began to walk away. But he came back and shot her three more times, said spokesman Sgt. Joe Narcisse.
Police say a surveillance camera captured the killing.
Johnson was arrested a short time later, said Narcisse, and handed over the officer's weapon without a struggle. He has been charged with murder, according to the New Orleans Times-Picayune.
"It's a somber but a very sobering occasion for us. It brings us back to the reality of police work. It's incredibly saddening considering the senselessness of the crime," Narcisse said.
New Orleans police said Johnson wasn't the suspect they were looking for in the rape case, and he had no outstanding warrants. The Associated Press reported he had been arrested numerous times on suspected sex offenses.
Cotton had been on the police force three years and was in the first police academy class to graduate after Hurricane Katrina.
"We will continue to police because we simply have to. It makes us take a step sideways, but we're not moving back," said Narcisse. "We recognize the danger. We mourn her loss. We can't stop. You don't stop the fight just because we're aching."
Cotton had transferred out of a central city precinct known as the Sixth District, but was moved back to that high-crime district two weeks ago.
Her funeral is scheduled for Friday in New Orleans. E-mail to a friend