SAN JUAN, Puerto Rico — The American Civil Liberties Union called on the U.S. Justice Department to take control of the Puerto Rican police force and ensure reforms are carried out in a report issued Tuesday that says the department's officers routinely use excessive force, killing at least 21 people in the past two years.

The ACLU says the department, the second-largest municipal police force among U.S. jurisdictions, has failed to address corruption, mismanagement and human rights abuses outlined in a scathing 2011 Department of Justice report. Puerto Rico's government had acknowledged problems with the department and agreed to undertake reforms.

"These abuses do not represent isolated incidents or aberrant behavior by a few rogue officers," the report said. "Such police brutality is pervasive and systemic, island-wide and ongoing. The Puerto Rico police department is steeped in a culture of unrestrained abuse and near-total impunity."

Police Chief Hector Pesquera dismissed the report in an interview with radio station WAPA.

"It's absolutely false. This is not a reflection of reality," said Pesquera, a former FBI official who became chief in April, replacing a National Guard general who held the post less than a year. "It is incorrect to say that the police dedicate themselves to violating the rights of citizens."

The ACLU report noted that between 2005 and 2010, more than 1,700 officers were arrested on charges including murder, drug trafficking and domestic violence. The number represents nearly 10 percent of the police force and is nearly three times the number of officers arrested in a comparable five-year period in the New York Police Department, which has more than twice as many officers.

"The human rights crisis in Puerto Rico is one of epic proportions," ACLU executive director Anthony Romero said. "We have the second largest police department in the country running amok ... If this were happening in any one of our major cities, this problem would not be allowed to languish."

William Ramirez, director of the ACLU in Puerto Rico, said the organization will file a lawsuit against the police department in upcoming weeks to seek reform.

Puerto Rico's government appointed a judge from the local Supreme Court as an independent monitor to oversee changes after the federal report came out, he said. "He issued a report and closed the office," Ramirez said.

In the past two years, the department says its officers have killed 21 people, including a 14-year-old boy and a 77-year-old man, but the ACLU believes the number is higher. In one case, a 22-year-old man who witnessed a robbery in September 2010 was giving police a statement when the gun of one officer at the scene accidentally went off, prompting another officer to fire 10 bullets, one which fatally hit the man in the back of the head.

From 2004 to 2010, civilians filed nearly 27,400 complaints against officers alleging misconduct, leading the department to recommend the expulsion of 884 officers. Of those complaints, at least 1,768 accused officers of excessive or unjustified force and assault, according to department statistics.

The ACLU recommended that the police department develop use of force policies and disciplinary sanctions, create procedures to investigate allegations of police abuse and establish an independent body to review complaints.

Romero, the ACLU executive director, said the Puerto Rican government has enacted only a few changes of the dozens sought by federal prosecutors.

He said the only solution is for the U.S. Justice Department to take receivership of the police force for as long as 15 years.

Among the Puerto Ricans who filed a complaint against police was Ruth Jimenez, whose son was killed by police in October 2007 under circumstances that have not been clarified, according to the ACLU.

Jorge Luis Polaco Jimenez, 28, was unarmed when he was shot eight times by officers, according to the ACLU. No one has been charged, and police maintain they acted in self-defense.

Ruth Jimenez said she has filed numerous complaints against the department and only recently obtained her son's autopsy after repeated failed attempts.

"I have had zero answers. Zero," she said in a phone interview. "I want the truth."

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