A review by Baltimore's police union on Wednesday criticized the police response to April rioting over the death of Freddie Gray after his arrest, saying commanders let unrest spiral into arson and looting.
A spokesman for Mayor Stephanie Rawlings-Blake rejected the evaluation by the Fraternal Order of Police Lodge 3, which represents more than 2,500 officers, as a "trumped-up political document."
The 32-page union review said police lacked riot equipment and training as well as direction from commanders in facing off against rock-throwing mobs and looters.
"The passive response ... allowed the disorder to grow into full-scale rioting," the review said.
Decisions by Police Commissioner Anthony Batts and aides "left officers in harm's way, making them vulnerable and susceptible to attack," it said.
Police have said about 160 officers were injured in rioting that erupted on April 27 after the funeral of Gray, a 25-year-old black man. He died of a spinal injury sustained while being transported in a police van.
Six officers have been charged in his death, which heightened a U.S. debate on police treatment of minorities.
Nearly 400 buildings were damaged or destroyed, and damage has been estimated in the millions of dollars. National Guard troops were dispatched and a curfew imposed to restore order.
Police commanders have said officers were ordered to hold their lines rather than confront people causing damage or threatening police.
Officials have said the orders were aimed at protecting officers and bystanders. Union officials have questioned that and requested access to communication records from commanders and City Hall.
In a statement, Kevin Harris, a Rawlings-Blake spokesman, said: "This report is no more than a trumped-up political document full of baseless accusations, finger pointing and personal attacks."
He said Baltimore had already taken steps to improve areas of weakness, including assessing riot gear and putting monitoring cameras in police transport vans.
Batts apologized to officers in May, saying he put them in harm's way.
Other reviews of police performance are being done by the department, aided by the Police Executive Research Forum, a non-profit policy group, and the International Association of Police Chiefs.
Police said on Tuesday that the forum would do its own evaluation.
Murders have surged in Baltimore since Gray's death, hitting 155 for the year versus 105 for the same period in 2014. Gunmen killed three people overnight near the University of Maryland, Baltimore, police said.