Image Michael Brown on his Facebook page.

Also on Tuesday, federal authorities learned the results of an autopsy performed on Mr. Brown by military coroners that showed that he had been shot six times, though they declined to release further details until their investigation was finished. An autopsy conducted on behalf of Mr. Brown’s family also found that he had been shot at least six times — including once in the face and once in the top of his head — with all bullets striking him in the front. The county has also done its own autopsy, which found evidence of marijuana in Mr. Brown’s system.

The Brown family has scheduled a funeral for Monday.

Clashes between the police and protesters have become a nightly ritual, although the scene on Tuesday was initially calm. The authorities took their positions before sunset, and Missouri National Guard soldiers staffed checkpoints at the shopping center that is now a police command post. Demonstrators marched without incident while officers watched. The quiet nature of the protests raised hopes that they had entered a calmer phase, but more confrontations were reported overnight, with 47 people arrested.

In a statement on Tuesday night, Gov. Jay Nixon expressed sympathy for the Brown family and praised residents for “standing against armed and violent instigators.” But he also said that “a vigorous prosecution must now be pursued.”

“The democratically elected St. Louis County prosecutor and the attorney general of the United States each have a job to do,” Mr. Nixon said. “Their obligation to achieve justice in the shooting death of Michael Brown must be carried out thoroughly, promptly and correctly, and I call upon them to meet those expectations.”