BATON ROUGE - Three law enforcement officers - two from the Baton Rouge Police Department and one from the East Baton Rouge Sheriff's Office - have been killed after six were shot in Baton Rouge Sunday morning, according to authorities from the East Baton Parish Sheriff's Office.

The lone suspected shooter is dead, according to Louisiana State Police.

Three officers were also injured -- one East Baton Parish Sheriff's deputy is in critical condition and two have non-life threatening injuries.

"We're grieving as a law enforcement community," said East Baton Rouge Sheriff Sid Gautreaux. "We're grieving for each other. We're grieving for our loss and we're grieving for our families."

"This is truly a sad day in Baton Rouge," said Kip Holden, the city's mayor-president said.

The three deceased officers were identified as Baton Rouge Police officers Matthew Gerald, 41, of Denham Springs, Montrell Jackson, 32, and Brad Garafola, 45, of the East Baton Rouge Parish Sheriff's Office.

President Barack Obama decried the incident, saying that it was just five days earlier that he attended a memorial for five Dallas Police officers who were slain by a gunman. "We as a nation have to be loud and clear that nothing justifies an attack on law enforcement," he said.

Initially, police reported there were several more suspects at large, but at a later press conference State Police Superintendent Mike Edmonson said authorities believed that the lone suspect was shot and killed by responding officers.

CBS News identified the shooter as 29-year-old Gavin Eugene Long of Missouri. Long reportedly committed the rampage on his birthday.

A witness said Eugene was clad in all black and wearing tactical gear, a ski mask and had extra magazine clips.

"There is not an active shooter scenario in Baton Rouge," he said during an afternoon press briefing. "We do believe, that based on the information that we have ... the person that shot and killed our officers that he is the person shot and killed at the scene."

"Shots fired. Officer down," a frantic officer can be heard calling on released audio.

Edmonson said several officers were shot around 8:40 a.m. Four minutes later a second call reported the officers were down. A call came into police reporting that a man, armed with a rifle, was walking near Airline Highway and Goodwin Boulevard.

"Baton Rouge Police officers at a convenience store observed the individual. He was wearing all black, standing behind a beauty supply store holding a rifle," Edmonson said. CBS News reported that the suspect was wearing body armor.

The exchange of gunfire took place between police and the suspect place at Benny's Car Wash and Oil Change next to the B-Quick convenience store by responding officers, where the suspect was shot and killed. Police could be seen checking the deceased suspect with a robot for explosives.

"At approximately 9:00 this morning Baton Rouge Police officers and East Baton Rouge Sheriff's deputies were involved in a shooting incident on Airline Highway near Old Hammond Highway. Multiple officers from both agencies sustained injuries and were transported to local hospitals," said the initial statement from the sheriff's office.

Reports of the shooting and possible suspects at large prompted authorities to ask the public to call 911 or local law enforcement agencies immediately if they saw anything suspicious and advised people to stay indoors. Edmonson is now asking people to stay aware and stay away from the crime scene while police investigated the situation.

During the time when police thought suspects were at large, two hospitals in Baton Rouge were placed on lockdown with police guarding the facilities and officers checking vehicles trying to enter the facility.

Around noon, Gov. John Bel Edwards, Holden, Col. Edmonson from State Police, Chief Carl Dabadie of the Baton Rouge Police Department and Sheriff Gautreaux all arrived at Our Lady of the Lake Hospital where some officers were taken to meet with family members. Those officials then met with media.

"We want and need your prayers," said Edmonson. "Baton Rouge is need of your prayers right now. "

A witness told WBRZ-TV that a man was dressed in black with his face covered shooting indiscriminately when he walked out between a convenience store and car wash across from Hammond Air Plaza. Police closed the streets between the police department’s headquarters and Interstate 12.

Holden asked for prayers for the officers and their families.

Gov. Edwards issued a statement on the attack."This is an unspeakable and unjustified attack on all of us at a time when we need unity and healing," he said.

"To me this is not so much about gun control as it is about what's in men's hearts," said Gautreaux.