FERGUSON, Mo. -- Police antagonized crowds gathered to protest in Ferguson, violated free-speech rights and made it difficult to hold officers accountable, according to a U.S. Department of Justice report summary obtained by CBS News.

The summary cited "vague and arbitrary" orders to keep protesters moving that violated their rights of assembly and free speech. It is part of a longer "after-action" report to be delivered this week to top police officials in Ferguson, St. Louis city and county and the Missouri State Highway Patrol.

The summary suggests that unrest that followed the shooting of 18-year-old Michael Brown was aggravated by the community's hostility toward Ferguson police and worsened when authorities didn't quickly divulge details of his death, the newspaper reported Tuesday.

"Had law enforcement released information on the officer-involved shooting in a timely manner and continued the information flow as it became available, community distrust and media skepticism would most likely have been lessened," according to the document.

Brown, who was black and unarmed, was fatally shot Aug. 9 by officer Darren Wilson, who is white. A grand jury and the Justice Department both declined to prosecute Wilson, who later resigned, but another Justice Department report released in March was critical of Ferguson police and the city's profit-driven municipal court system.

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The after-action report, which then-Attorney General Eric Holder announced in September, looks at the way the four agencies responded in the first 16 days after the shooting and is separate from other federal civil rights inquiries into Brown's death and the overall policing practices of the Ferguson force, and done by the Justice Department's Community Oriented Policing Services office.

The new report, which the newspaper said is subject to revision, cited other problems, too: The use of dogs for crowd control incited fear and anger, and the DOJ suggested that the practice be prohibited. The report also said that tear gas was sometimes used without warning on people who had nowhere to retreat.

There were inconsistencies in the way police used force and made arrests, the report said, having dedicated "officer training on operational and tactical skills without appropriate balance of de-escalation and problem-solving training."

The full report is expected to contain about 45 "findings," each including a recommendation for improvement, the Post-Dispatch reported.

St. Louis Police Chief Sam Dotson told the newspaper he didn't have enough information yet to comment on the report, but that he hopes that it provides a blueprint for dealing with similar situations in the future.

St. Louis County chief Jon Belmar declined to comment, saying he would address his concerns directly to federal officials.

The city of Ferguson issued a statement saying officials are "reviewing these latest findings and will act accordingly." The Missouri Department of Public Safety, which oversees the highway patrol, did not respond to the newspaper's request for comment.

The summary found that from the beginning, use of a "highly elevated tactical response" set a tone that "limited options for a measured, strategic approach." It acknowledges that a tactical response was sometimes called for, but an "elevated daytime response was not justified and served to escalate rather than de-escalate the overall situation."

The report also found that police "underestimated the impact social media had on the incident and the speed at which both facts and rumors were spread and failed to have a social media strategy."