Mayor Michael Bloomberg answered his critics on Sunday with a defiant defense of his comments that the New York Police Department doesn't stop minorities often enough based on murder suspect descriptions.

“The numbers are the numbers, and the numbers clearly show that the stops are generally proportionate with suspects' descriptions and for years now critics have been trying to argue that minorities are stopped disproportionately,” he said before the city's gay-pride march Sunday. “If you look at the crime numbers, that is just not true. The numbers don't lie.”

The comments, and the mayor's defense of them, have touched a nerve, sparking a deluge of criticism. Mr. Bloomberg's NYPD ramped up the stop-and-frisk tactic, conducting more than five million stops since the mayor took office in 2002—the vast majority of them being young black and Hispanic men.

The tactic has become a flash point in the campaign to succeed Mr. Bloomberg. On Sunday, Democratic candidates again seized on the opportunity to criticize the mayor.

“Suggesting we could have more stops of blacks and Latinos is a slap in the face,” said Public Advocate Bill de Blasio.

Former U.S. Rep. Anthony Weiner said: “It just shows that the mayor doesn't quite understand and he needs to try to show some understanding to the people who have these legitimate complaints.”

Mr. Bloomberg, who is scheduled to step down on Dec. 31 after 12 years as mayor, said he could have made the point “more clearly.” But he mocked his critics as trying to score points during a political season.

“I understand that we're in a campaign season and everybody wants to do something right for their campaign, rather than help us get out of this terrible situation where a disproportionate percentage of the crime is committed by a group of young kids that just don't have any future,” said Mr. Bloomberg, referring to minorities.

The imbroglio began on Friday during the mayor's radio show, when Mr. Bloomberg said the NYPD disproportionately stops whites too much and minorities too little. He said critics' argument that minorities are stopped disproportionately is “exactly the reverse” of what the numbers show.

On Friday, City Hall backed up the mayor's arguments by touting statistics that showed whites were involved in 9% of police stops in 2012, but were identified as 7% of murder suspects.

The tactic has drawn wide scrutiny and is the target of three class-action lawsuits in federal court. A judge is expected to decide in the coming months whether the mayor's administration has violated New Yorkers' constitutional rights.

On Thursday, the City Council voted to appoint an inspector general to monitor the NYPD and to allow people to file claims of racial profiling against the police in state court. Mr. Bloomberg plans to veto both measures, and he has pledged to wage a vigorous battle to prevent the council from overriding his veto.

Council Member Brad Lander, a top sponsor of both bills, said the mayor's “tin-eared intransigence just makes [the legislation] more necessary and more likely that we will override his veto.”

U.S. Rep. Hakeem Jeffries, whose district includes parts of Brooklyn and Queens with the highest rates of crime, called on Sunday for a federal monitor of the NYPD on stop-and-frisk.

Mr. Jeffries said Mr. Bloomberg's “racially charged comments” last week showed he doesn't recognize the pain caused by the policy and that “the time is now” for its reduction. “The mayor's comments in defense of stop-and-frisk were sad, disrespectful, hurtful, and quite unfortunate,” he said.

—Erica Orden and Joe Jackson contributed to this article.