(CNN) — Abdullah Muflahi, the owner of the convenience store where Alton Sterling was shot to death, is suing the city of Baton Rouge, Louisiana and its police department.

According to the suit, Muflahi accuses authorities of illegally taking him into custody and confiscating his entire security system without a warrant.

When asked about the lawsuit by CNN, Cpl. L’Jean McKneely said police would not comment on pending litigation, as is standard procedure.

The state is investigating the controversial death of Sterling, a black man who was fatally shot after he was pinned down by two Baton Rouge police officers.

The U.S. Department of Justice is leading a criminal investigation, Louisiana Gov. John Bel Edwards said. The FBI and state police also will be involved, and a federal civil rights investigation will be conducted.

Any consideration of state charges would come after the results of the federal investigation, East Baton Rouge District Attorney Hillar C. Moore said.

Moore recused himself and his office from the case on Monday, citing a possible conflict of interest.

“It is my determination as District Attorney that given the history of a long and close working relationship with the parents of one of the officers involved in this shooting, there would always be questions of my partiality,” Moore said.

He said the state attorney general could accept the case himself, appoint another district attorney or choose an independent prosecutor.

The deaths of Sterling and Philando Castile — both of whom were shot and killed by police — touched off massive protests in the United States.

On Thursday, Micah Xavier Johnson killed five Dallas police officers who were near protests against police misconduct.

The carnage could have been much worse

During his hourslong standoff with police, Johnson said he was ready to kill more cops with bombs, Dallas police Chief David Brown told CNN.

“We had negotiated with him for about two hours, and he just basically lied to us — playing games, laughing at us, singing, asking how many (police officers) did he get and that he wanted to kill some more and that there were bombs there,” Brown said.

A search of the gunman’s home revealed he had plenty of supplies to make explosives. Brown said police found bomb-making materials and a journal that suggested Johnson had been practicing detonations and appeared ready to take aim at larger targets.

It was enough, Brown said, to have “devastating effects on our city.”

He ‘liked’ a group that called for violence against police

A day before Johnson opened fire on police, the African American Defense League called for action after Sterling’s death.

“The Pig has shot and killed Alton Sterling in Baton Rouge, Louisiana!” the group’s Facebook post said. “You and I know what we must do and I don’t mean marching, making a lot of noise, or attending conventions. We must “Rally The Troops!” It is time to visit Louisiana and hold a barbeque. The highlight of our occasion will be to sprinkle Pigs Blood!”

The group also issued and then quickly deleted another post-Thursday, “calling on the gangs across the nation! Attack everything in blue…”

Johnson “liked” the group’s page. He also had visited the websites of the Nation of Islam and the Black Riders Liberation Party — which the Southern Poverty Law Center considers to be hate groups.

Tom Fuentes, a former associate director with the FBI, said the messages and the groups behind them should be treated the same way the federal government investigates ISIS.

“It’s no different than the ISIS propaganda that goes out,” Fuentes said. “And the question for law enforcement is, where do you draw the line between free speech and something else? If a message is espousing someone to take action, even if they inspire one guy to strike out, isn’t that enough?”

Hundreds of statements, mountains of footage

Detectives are reviewing more than 300 statements from witnesses and officers from the scene, Brown said.

Police have 170 hours of body camera footage to download and analyze, the chief said.

Though swaths of downtown remain closed, some streets are scheduled to reopen Tuesday, according to police.

But many questions remain, including the meaning of the letters “RB.” The killer wrote those letters twice on a wall — using his own blood — before he was killed by a police bomb, Brown said.

Johnson was wearing a bulletproof vest and had three weapons on his body, a law enforcement source familiar with the investigation said.

Those weapons included a Glock 19 Gen4 pistol, a Fraser .25-caliber handgun and an Izhmash Saiga semiautomatic, assault-style rifle.

A second law enforcement official said it appears all the weapons were purchased legally, and that some were bought online.

Gunman’s parents: He wanted to be a police officer

The killings of five officers came as a horrific shock to Johnson’s parents — especially because the Army veteran had wanted to be an officer when he was younger, his mother said.

“He loved his country,” Delphine Johnson said in an interview with The Blaze. “He wanted to protect his country.”

But his demeanor and attitude changed drastically after his six-year military service, which included seven months in Afghanistan, Johnson’s mother told The Blaze. She said he morphed from a gregarious extrovert to a “hermit.”

The gunman’s father, James Johnson, said his son started delving into black history after he was honorably discharged last year. But he had no clue

“I don’t know what to say to anybody to make anything better. I didn’t see it coming,” James Johnson told The Blaze. “I love my son with all my heart. I hate what he did.”

Answers wanted in Philando Castile’s death

In Minnesota, relatives of Philando Castile are trying to understand why an officer killed the school nutrition services supervisor during a traffic stop. Castile’s fiancée broadcast the aftermath of the shooting on Facebook Live.

“He let the officer know that he had a firearm and he was reaching for his wallet and the officer just shot him in his arm,” Diamond Reynolds said in her Facebook broadcast. “… You shot four bullets into him, sir. He was just getting his license and registration, sir.”

St. Anthony police don’t have body cameras, office manager Kim Brazil said. The investigation is ongoing.

“We will release the information as we learn it,” Sgt. Jon Mangseth said, “and we will address concerns as we are faced with them.”

Tom Kelly, a lawyer for Jeronimo Yanez — the officer involved in the fatal shooting — told CNN that the Castile matched the description of a suspect involved in an armed robbery.

“The driver of the vehicle largely matched the description of an armed robbery incident that happened in the vicinity of this stop, several days prior to this stop which aroused in Officer Yanez a reasonable suspicion to take further investigative steps leading to the stop of the vehicle,” Kelly said.

CNN’s Drew Griffin, David Fitzpatrick, Curt Devine, Catherine E. Shoichet, Jake Tapper, Scott Glover, Dave Alsup, Nick Valencia, Linh Tran and Mary Kay Mallonee contributed to this report.