Updated

Police in the St. Louis suburb of Ferguson, Mo. used tear gas and smoke bombs Wednesday to disperse protesters, some of whom threw Molotov cocktails and other objects at officers, as a fifth night of demonstrations over the fatal shooting of an unarmed black teenager by a police officer turned violent.

Protesters faced heavily armed police who occasionally trained automatic weapons on them from an armored truck. After nightfall, the situation deteriorated, with police ordering demonstrators to go home before using smoke bombs and later tear gas. There were no immediate reports of injuries.

The St. Louis Post-Dispatch reported that police inched forward to disperse the main body of protesters into small groups pushed down side streets. The paper reported that some people were unable to get to their homes.

Earlier in the evening, two reporters were arrested and briefly held after police officers attempted to clear a McDonald's restaurant where they were working. Wesley Lowery of The Washington Post and Ryan Reilly of The Huffington Post said they were handcuffed and put into a police van. The Post reported that Lowery said he was slammed against a soda machine and plastic cuffs were put on his wrists. The reporters were subsequently released without any charges.

Martin Baron, the Post's executive editor, issued a statement saying "there was absolutely no justification" for Lowery's arrest and said the organization was appalled by the officers' conduct.

Ryan Grim, Washington, D.C., bureau chief for The Huffington Post, said in a statement that "compared to some others who have come into contact with the police department, they came out relatively unscathed, but that in no way excuses the false arrest or the militant aggression toward these journalists."

The protests stemmed from Saturday's fatal shooting of 18-year-old Michael Brown, whom police have said was shot after an officer encountered him and another man on the street. They say one of the men pushed the officer into his squad car, then physically assaulted him in the vehicle and struggled with the officer over the officer's weapon. At least one shot was fired inside the car. The struggle then spilled onto the street, where Brown was shot multiple times. In their initial news conference about the shooting, police didn't specify whether Brown was the person who scuffled with the officer in the car and have refused to clarify their account.

Ferguson Police Chief Tom Jackson said Wednesday that the officer involved sustained swelling facial injuries.

Dorian Johnson, who says he was with Brown when the shooting happened, has told a much different story. He has told media outlets that the officer ordered them out of the street, then tried to open his door so close to the men that it "ricocheted" back, apparently upsetting the officer. Johnson says the officer grabbed his friend's neck, then tried to pull him into the car before brandishing his weapon and firing. He says Brown started to run and the officer pursued him, firing multiple times. Johnson and another witness both say Brown was on the street with his hands raised when the officer fired at him repeatedly.

Some protesters Wednesday raised their arms above their heads as they faced the police. Others held signs asking for answers about Brown's death. The most popular chant has been, "Hands up! Don't shoot!"

Brown's body remained on the street for hours -- a span Jackson deemed "uncomfortable" but justified, given that "you only get one chance at that crime scene" to process it correctly. Jackson said authorities also were concerned about gunfire they could hear in a nearby building.

In the shooting's aftermath, the notorious hacking collective Anonymous has taken credit for burrowing into the city website and shutting it down for much of the day Monday. The group also released what it said were audio experts from St. Louis County dispatch on the day Brown was killed. Police declined to comment on the recordings Wednesday.

Authorities have resisted calls to identify the officer who shot Brown, citing a fear of retribution, and have also said there is no police or security video of the confrontation.

Earlier Wednesday, Jackson told reporters earlier in the day that the St. Louis County investigation of the shooting could take weeks to complete. In the meantime, he said, his department welcomes Justice Department training on racial relations in the suburb, where two-thirds of the 21,000 residents are black while all but three of the police force's 53 officers are white.

"Unfortunately, an undertow (of racial unrest) has bubbled to the surface," said Jackson. "Race relations is the top priority right now."

The Associated Press contributed to this report. 

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