Update 9.20am: Republican presidential hopeful Donald Trump has said a "lack of leadership" was to blame for the shootings.
Mr Trump said in a statement posted on his Twitter and Facebook pages: "We grieve for the officers killed in Baton Rouge today.
"How many law enforcement and people have to die because of a lack of leadership in our country? We demand law and order."
Update: 8.40pm: US President Barack Obama said he condemns, in the strongest sense of the word, the attack on police officers in Baton Rouge.
Mr Obama said the attacks on police officers, the second in two weeks, are "attacks on public servants, on the rule of law, and on civilised society, and they have to stop".
Update: 7.55pm: Three US police officers have been killed and three others were wounded after a shooting in Baton Rouge, Louisiana.
One suspect has been killed, but law enforcement officials believe two others might still be at large, with the city on high alert.
The shooting, which took place just before 9am local time (3pm BST) less than one mile from police headquarters, comes amid spiralling tensions across the city and the wider country between the black community and police.
The races of the suspects and the officers has not been revealed.
The incident comes less than two weeks after a black man was shot and killed by police in Baton Rouge, sparking nightly protests across the city.
Louisiana governor John Bel Edwards rushed to the hospital where the shot officers had been taken.
He said: "Rest assured, every resource available to the State of Louisiana will be used to ensure the perpetrators are swiftly brought to justice."
The shooting took place at a petrol station near a fitness centre on Airline Highway, where the slain shooter's body is being searched for explosives with the use of a specialised robot.
Earlier: Media reports have stated that multiple police officers has been shot in Baton Rouge, Louisiana.
Three police officers have been reported dead following a shooting and four more are injured.
Baton Rouge police sergeant Don Coppola said earlier that the officers were rushed to a local hospital. Sgt Coppola said authorities are asking people to stay away from the area.
Multiple police units were stationed at Our Lady of the Lake Regional Medical Centre, where stricken officers were believed to be undergoing treatment at a trauma centre. A police officer with a long gun was blocking the parking lot at the emergency room.
Officers and deputies from the Baton Rouge police department and East Baton Rouge sheriff's office were involved, according to Ms Hicks.
The shooting happened early, 9am, on Sunday, less than one mile from police headquarters.
BREAKING: Authorities in Louisiana say more than 1 police officer has been shot in Baton Rouge.— The Associated Press (@AP) July 17, 2016
A reporter on the scene saw police vehicles with lights flashing massed about a half mile from the police headquarters on Airline Highway. Police armed with long guns on the road stopped at least two vehicles driving away from the scene and checked their trunks and vehicles before allowing them to drive away.
The incident has occurred five miles from where black man Alton Sterling was shot dead outside a convenience store by American police officers earlier this month.
The killing was captured on a mobile phone video and circulated widely on the internet.