CHICAGO/ORLANDO, Fla. (Reuters) - U.S. President Donald Trump pledged on Monday to end a “crime spree” in Chicago and called for loosening restrictions on police in the third-largest U.S. city to allow stopping and frisking suspects for weapons and other contraband.

Chicago police agreed in August 2015 to outside monitoring of stop-and-frisk searches after an American Civil Liberties Union report that found officers stopped a disproportionate number of black people and relied on the practice more heavily than departments in other cities.

Trump’s remarks came three days after a white Chicago police officer was found guilty of murder in the 2014 shooting of a black teenager, a case that laid bare tensions between the city’s black community and police department.

Proponents say stop-and-frisk helps prevent violent crime by taking more illegal guns and other contraband off the streets. Opponents say black people and members of other minority ethnic groups are unfairly targeted by the stops.

Trump said he had directed the U.S. attorney general “go to the great city of Chicago to help straighten out the terrible shooting wave,” without providing details.

“I’ve told them to work with local authorities to try to change the horrible deal the city of Chicago’s entered into with ACLU, which ties law enforcement’s hands and to strongly consider ‘stop and frisk,’” Trump said at the International Association of Chiefs of Police convention in Orlando, Florida.

“It works and it was meant for problems like Chicago. It was meant for it.”

FILE PHOTO: Yellow police tape is displayed at a crime scene after a motorist was shot in the head along the 2700 block of south 80th Street in Chicago, Illinois, U.S., November 1, 2017. REUTERS/Joshua Lott/File Photo

His comments were a reprise of a vow made last year to bring federal help to fight Chicago’s crime.

The Justice Department referred questions about Trump’s comments to the White House, which did not respond to requests for comment.

The office of Mayor Rahm Emanuel took issue with the president, saying the number of murders and shooting victims in Chicago declined for the past two straight years. In 2016, the number of homicides spiked to 771, a rise of nearly 60 percent from the previous year.

“Even someone as clueless as Donald Trump has to know stop-and-frisk is simply not the solution to crime,” Matt McGrath, a spokesman for the mayor, said in an emailed statement.

On Friday, white Chicago police officer Jason Van Dyke was found guilty of second-degree murder for the shooting of black teenager Laquan McDonald.

Van Dyke, 40, was also convicted of 16 counts of aggravated battery, one count for each of the shots fired. McDonald, 17, was killed while armed with a knife.

A dashboard camera video, released more than a year after the Oct. 20, 2014, incident in response to a Freedom of Information Act lawsuit filed by a journalist, sparked days of protests in Chicago, led to the firing of Chicago Police Superintendent Garry McCarthy and prompted calls for Emanuel to resign.

A Justice Department investigation that began after the video’s release found Chicago police routinely violated people’s civil rights, citing excessive force and racially discriminatory conduct. As a result of the probe, the Illinois attorney general and city officials filed last month a proposed consent decree in federal court to reform the police department.

Emanuel, a former White House chief of staff to President Barack Obama who became mayor in 2011, said on Sept. 4 he would not seek re-election next year. He has faced widespread criticism over his handling of gun violence.

In 2013, a federal judge ruled that the New York Police Department’s use of stop and frisk tactics disproportionately targeted black and Hispanic people, saying police had violated the U.S. Constitution’s protections against unreasonable searches.