BATON ROUGE, La. -- A Missouri man ambushed and killed three law officers and wounded three others in Baton Rouge on Sunday during a time when police nationwide and in the Louisiana city in particular have been on high alert after five officers were killed in a Dallas ambush July 7.
Louisiana State Police announced last week that they had received credible threats of lethal plots against Baton Rouge police and had arrested three men and a 13-year-old boy.
On Sunday, a man identified as Gavin Long of Kansas City went on a shooting rampage on his 29th birthday that left two police officers and a sheriff's deputy dead, police sources said. Long was a former Marine who spent time in Iraq and was discharged at the rank of sergeant in 2010, according to the U.S. military.
Police have not released the names of the victims but one was identified by family members as Officer Montrell Jackson, according to Jackson's aunt.
"Today isn't going too well," she said.
Responding police officers killed Long, who was born on July 17, 1987, in a gunbattle after the other officers were ambushed, police sources told CNN.
Two Baton Rouge police officers -- ages 41 and 49 -- died, said Police Chief Carl Dabadie. The gunman also killed a 45-year-old sheriff's deputy and critically wounded a 41-year-old deputy who is "fighting for his life," said East Baton Rouge Parish Sheriff Sid Gautreaux.
Another wounded deputy and police officer have non-life-threatening wounds, law officers said.
At an afternoon news conference, local and state authorities, including Louisiana Gov. John Bel Edwards, said Long was thought to be the lone gunman. Earlier reports had said authorities believed there might have been more than one attacker.
There is not an "active shooter scenario" in Baton Rouge, said Col. Michael D. Edmonson, superintendent of the Louisiana State Police.
President Barack Obama on Sunday condemned the killings and all attacks on law enforcement.
"We as a nation have to be loud and clear that nothing justifies violence against law enforcement," Obama said, speaking from the White House press briefing room. "Attacks on police are an attack on all of us and the rule of law that makes society possible." In a written statement earlier in the day, Obama called the Baton Rough shootings a "cowardly and reprehensible assault."
The shooting Sunday took place around 8:40 a.m. (9:40 a.m. ET) in the city of about 230,000 people, already tense after a high-profile police shooting of Alton Sterling, an African-American man, on July 5.
On Sunday, police received a call of a "suspicious person walking down Airline Highway with an assault rifle," a source with knowledge of the investigation told CNN.
When police arrived, the shooting began.
"There was no talking, just shooting," Baton Rouge Police Cpl. L.J. McKneely said.
By noon, authorities had secured the scene and were making sure there weren't any explosives left behind.
Initially authorities believed two other shooters might be at large.
Long was wearing all black and was wearing a mask, Baton Rouge Police Department Sgt. Don Coppola said. Coppola said he did not know what the mask looked like, but that it was "some type of mask to conceal (the shooter's) identity."
Since the shooting death of Sterling by Baton Rouge police, the department has worried about threats against officers.
It has been an emotionally charged few days across the country because of the protests stemming from the Sterling shooting and the shooting by police of Philando Castile in Minnesota, plus the ambush on Dallas police officers in which a sniper killed five officers.
"This is an unspeakable and unjustified attack on all of us at a time when we need unity and healing," Edwards said Sunday in the hours after the Baton Rouge shooting.