Police said their aggressive actions were prompted by a suspect in a burglary saying he and others stole several guns "to harm police officers", Baton Rouge Police Chief Carl Dabadie Jr. said at a news conference Tuesday.
Three people were arrested this week in connection to a plot thought to be a retaliation against police officers in Baton Rouge, reports said.
State Police Superintendent Mike Edmonson said information regarding the plot revealed "an actual, credible threat" against police.
The chief said the first suspect arrested told police that "the reason the burglary was being done was to harm police officers".
Local and state law enforcement agencies have run roughshod over the First Amendment in dealing with protesters in the wake of Alton Sterling's July 5 shooting death at the hands of Baton Rouge police, Louisiana's leading civil liberties organization and local organizing groups alleged Wednesday in a federal lawsuit.
Demonstrators have criticized police for wearing full riot gear and detaining some leaders of the protests.
Alton Sterling's son spoke of the protests while addressing reporters Wednesday morning.
However, they used the plot to kill officers, which they described as "real, credible evidence" that police were under a serious threat, as their justification for how law enforcement had handled protests in the city over the weekend.
A temporary restraining order also was requested to prevent police "from interfering with people's constitutionally protected right to gather peacefully moving forward", the ACLU said in a news release. "Most of the protesters tried to obey police orders to stay out of the roadway, even backing off a grassy strip next to the road when police told them to move onto the sidewalk".
The police have come under fire for tactics they used on protesters over the weekend.
Since Saturday, detectives have arrested two other suspects in the case, including a 13-year-old boy.
Louisiana Chapter of the National Lawyers Guild President and Catholic nun Alison Renee McCrary: "I witnessed firsthand as peaceful protestors [sic] were violently attacked and arrested, assault weapons pointed at them with fingers on the triggers, some dragged across the cement, their clothes ripped off of them". They called on a fourth suspect to turn himself in. "Well, this is the reason, because we had credible threats against the lives of law enforcement in this city", Dabadie said. He said the riot gear and weaponry were appropriate.
In a statement Monday, Landry said he won't have access to details of the federal investigation of Sterling's shooting until it's completed and a decision has been made on potential federal charges. "Yet Alton Sterling is on the long list of Black people killed needlessly by our nation's police, and protests in his honor have turned into circuses of violence where the First Amendment is tossed aside", said ACLU of Louisiana Executive Director Marjorie Esman.