Three police officers have been killed and three more injured in a shooting in Baton Rouge, Louisiana. A suspected gunman was also killed and police were searching for two possible accomplices. A local news station has said that police are in a stand-off with one of the suspected accomplices.

Authorities said the six law enforcement officials were hit by gunfire, in the US city that has been the focus of tensions since the killing of an African-American man at the hands of police earlier in July.

The shooting took place in the Old Hammond area near police headquarters and Airline Highway at around 9am local time. Images from the scene showed heavy police presence near a road intersection. Gunfire could be heard in the background of footage captured with a mobile phone.

"There is still an active scene. They are investigating. Right now we are trying to get our arms around everything. It's just been one thing after another," Parish Kip Holden, the mayor-president of East Baton Rouge, told the CNN.

The injured law enforcement officials were taken to the local Our Lady of the Lake hospital, he added.

The East Baton Rouge Sheriff's Office advised the public to avoid the area and if nearby remain indoors contact authorities "immediately if they see anything suspicious".

Louisiana governor John Bel Edwards described the incident as an "unspeakable and unjustified attack".

WAFB, a local news channel serving Louisiana, has reported that one of the fugitive suspects is in a standoff with local police forces. The location of the siege is not known.

Anger at police shootings

The shooting came less than 48 hours after the funeral of Alton Sterling, a 37-year-old black man who was shot killed by police outside a convenience store in the city on 5 July.

His death was captured on camera leading to protests across the US.

A few days later, Micah Johnson, an African-American army veteran angered at Sterling's killing and a similar police shooting in Minnesota, which saw Philando Castile killed in his car by a police officer, gunned down five police officers in Dallas, Texas, in a revenge attack.

It was not immediately clear if the events were directly related.

Baton Rouge
Police officers block off a road after a shooting of police in Baton Rouge, Louisiana Reuters