hormones, adolescent stupidity and sheer boredom...,

NYTimes |  The Highway Patrol officer named to take over security in Ferguson, Capt. Ronald S. Johnson, also expressed his displeasure with how the information had been released. Captain Johnson, who grew up in the area, had been brought in by Gov. Jay Nixon on Thursday to restore peace after days of confrontations between demonstrators and the police in riot gear and military-style vehicles. The captain said he had not been told that the authorities planned to release the video of the robbery along with the name of the officer. But he sought to calm people down, saying, “In our anger, we have to make sure that we don’t burn down our own house.”

Protests on the streets Friday night started peacefully. Cars clogged streets as horns blared and music played. Hundreds of demonstrators clutched signs and chanted slogans, but many others danced to music. On one street, six people danced atop a delivery truck.

Although the police presence was limited, Captain Johnson walked through the community, taking photographs with children and offering hugs and handshakes. “I’m pleased with how it’s going,” he said early in the night.

But tensions rose around midnight when the police released a small amount of tear gas as they backed away from the crowd. Some protesters threw rocks and other objects, according to media reports. Some demonstrators fired weapons into the air.

Captain Johnson told The Associated Press that the police backed off to try to ease the tension. “We had to evaluate the security of the officers there and also the rioters,” he told The A.P. “We just felt it was better to move back.”

Using people and vehicles, protesters quickly blocked a major thoroughfare here, prompting the police to return and form a barricade of their own. For a time, the protesters and the police faced off in the road. The police urged protesters to go home, and demonstrators, many of them chanting slogans like “We ready for y’all,” approached the officers. Some tossed glass bottles toward the police.