WASHINGTON — In a blistering condemnation of the second-largest police force in the United States, the Justice Department is accusing the Puerto Rico Police Department of a “profound” and “longstanding” pattern of civil rights violations and other illegal practices that have left it “broken in a number of critical and fundamental respects.”

In a 116-page report that officials intend to make public Thursday, the civil rights division of the Justice Department accused the Puerto Rico Police Department of systematically “using force, including deadly force, when no force or lesser force was called for,” unnecessarily injuring hundreds of people and killing “numerous others.”

The report, a copy of which was obtained by The New York Times, says the 17,000-officer force routinely conducts illegal searches and seizures without warrants. It accuses the force of a pattern of attacking nonviolent protesters and journalists in a manner “designed to suppress the exercise of protected First Amendment rights.”

And it says investigators “uncovered troubling evidence” that law enforcement officers in Puerto Rico appear to routinely discriminate against people of Dominican descent and “fail to adequately police sex assault and domestic violence” cases — including spousal abuse by fellow officers.