A grand jury declined to indict police officer Darren Wilson in the death of Michael Brown, once again sparking riots in Ferguson, Missouri.

Moments after the announcement by St. Louis County’s top prosecutor on Monday, crowds began pouring into Ferguson streets to protest the decision. Some taunted police, broke windows and vandalized cars.

Within a few hours, several large buildings were ablaze, and frequent gunfire was heard. Officers used tear gas to try to disperse some of the gatherings.

Prosecuting Attorney Bob McCulloch said the jury of nine whites and three blacks met on 25 separate days over three months, hearing more than 70 hours of testimony from about 60 witnesses, including three medical examiners and experts on blood, toxicology and firearms. McCulloch says Officer Wilson was among those who testified, saying Mr Brown matched the description of a robbery suspect, that Brown hit the officer and tried to take his service weapon.

Federal Aviation Administration flight restrictions in the St. Louis area have been lifted. Lambert-St. Louis International Airport spokesman Jeff Lea said the restrictions expired at 3:30 a.m.

Lea said about 10 inbound flights were canceled or diverted late Monday because of reports of gunshots fired into the sky following the grand jury’s decision not to return an indictment.

The FAA said Monday the restriction was meant “to provide a safe environment for law enforcement activities.”

Lea said the airport expected to see full operations Tuesday. Six outbound flights were canceled Tuesday morning largely because the planes to be used didn’t land last night.

For two weeks after the shooting, the FAA restricted flights on 37 square miles of airspace, including for news helicopters.