BATON ROUGE, La. — Three Baton Rouge law enforcement officers investigating a report of a man with an assault rifle were killed Sunday, less than two weeks after a black man was fatally shot by police here in a confrontation that sparked nightly protests that reverberated nationwide.
Three other officers were wounded, one critically. Police said the gunman was killed at the scene. Although he was believed to be the only person who fired at officers, authorities said they were unsure whether he had some kind of help.
"We are not ready to say he acted alone," state police spokesman Major Doug Cain said. Two "persons of interests" were detained in the nearby town of Addis.
A law enforcement official familiar with the investigation identified the shooter as Gavin Long, a 29-year-old Kansas City, Missouri, man. The official spoke on condition of anonymity because the official was not authorized to discuss an ongoing investigation.
Kansas City police, some with guns drawn, converged on a house listed as Long's.
The University of Alabama issued a statement saying that Long attended classes for one semester in spring of 2012. School spokesman Chris Bryant said university police had no interactions with him.
One witness described a gunman who was wearing all black and carrying extra clips of ammunition. The races of the suspect and the officers were not immediately known.
The shooting — which took place just before 9 a.m., less than a mile from police headquarters — came amid escalating tensions across the country between the black community and police. Just days earlier, one of the slain officers posted an emotional Facebook message about the challenges of police work in the current environment.
It was the fourth high-profile deadly encounter in the United States involving police over the past two weeks. In all, the violence has cost the lives of eight officers, including those in Baton Rouge, and two civilians and sparked a national debate over race and policing.
President Barack Obama urged Americans to tamp down inflammatory words and actions.
"We as a nation have to be loud and clear that nothing justifies attacks on law enforcement," Obama said in remarks from the White House. "Everyone right now focus on words and actions that can unite this country rather than divide it further."
Authorities initially believed that other assailants might be at large, but hours later said that no other active shooters were on the loose. They did not discuss the gunman's motive or any relationship to the wider police conflicts.
The shooting began at a gas station on Airline Highway. According to radio traffic, Baton Rouge police answered a report of a man with an assault rifle and were met by gunfire. For several long minutes, they did not know where it was coming from.
The radio exchanges were made public Sunday by the website Broadcastify.
Nearly 2½ minutes after the first report of an officer getting shot, an officer on the scene is heard saying police do not know the shooter's location.
Almost six minutes pass after the first shots are reported before police say they have determined the shooter's location. About 30 seconds later, someone says shots are still being fired.
The recording lasts about 17 minutes and includes urgent calls for an armored personnel carrier called a BearCat.
The officers who were shot worked for the Baton Rouge Police Department and the East Baton Rouge Sheriff's Office.
"There simply is no place for more violence," Gov. John Bel Edwards said. "That doesn't help anyone. It doesn't further the conversation. It doesn't address any injustice perceived or real. It is just an injustice in and of itself."
From his window, Joshua Godwin said he saw the suspect, who was wearing all black with a ski mask, combat boots and extra bullets. He appeared to be running "from an altercation."
Mike Spring awoke at a nearby house to a sound that he thought was from firecrackers. The noise went on for five to 10 minutes, getting louder.
Of the two officers who survived the shooting, one was hospitalized in critical condition, and the other was in fair condition. Another officer was being treated for non-life-threatening injuries, hospital officials said.
Officer Montrell Jackson posted his message on Facebook on July 8, just three days after the death of 37-year-old Alton Sterling, a black man killed by white Baton Rouge officers after a scuffle at a convenience store.
In the message, Jackson said he was physically and emotionally tired and complained that while in uniform, he gets nasty looks.
A friend of Jackson's family, Erika Green, confirmed the posting, which is no longer on Facebook. A screenshot of the image was circulating widely on the internet.
The Baton Rouge attack unfolded hours after a domestic violence suspect opened fire early Sunday on a Milwaukee police officer who was sitting in his squad car. The officer was seriously wounded, and the suspect fled and apparently killed himself, authorities said.
Police-community relations in Baton Rouge have been especially tense since Sterling's death. The killing was captured on cellphone video.
It was followed a day later by the shooting death of another black man in Minnesota, whose girlfriend livestreamed the aftermath of his death on Facebook. The next day, a black gunman in Dallas opened fire on police at a protest about the police shootings, killing five officers and heightening tensions even further.
Thousands of people have protested Sterling's death, and Baton Rouge police arrested more than 200 demonstrators.
Sterling's nephew condemned the killing of the three Baton Rouge officers. Terrance Carter spoke Sunday to The Associated Press by telephone, saying the family just wants peace.
"My uncle wouldn't want this," Carter said. "He wasn't this type of man.
A few yards from a police roadblock on Airline Highway, Keimani Gardner was in the parking lot of a warehouse store that would ordinarily be bustling on a Sunday afternoon. He and his girlfriend both work there. But the store was closed because of the shooting.
"It's crazy. ... I understand some people feel like enough is enough with, you know, the black community being shot," said Gardner, an African-American. "But honestly, you can't solve violence with violence."
Michelle Rogers and her husband drove near the shooting scene, but were blocked at an intersection closed by police.
"I can't explain what brought us here," she said. "We just said a prayer in the car for the families."