Carlos Osorio / AP Detroit Interim Police Chief Chester Logan answers a question as Mayor Dave Bing looks on during a news conference in Detroit on Thursday.

The homicide rate in the city of Detroit continued a grim upward trend in 2012, hitting its highest peak in nearly two decades, officials said Thursday.

A dwindling population -- 706,585 people in 2011, according to the U.S. Census estimate -- and the rise in homicides combined to make Detroit’s murder rate among the highest in the nation, Detroit Mayor Dave Bing and Police Chief Chester Logan announced at a press conference.

“We’ve just lost respect for each other; we’ve lost respect for life,” Bing said. “I don’t want to say that you can forget about this generation or the generation before us, but if we’re going to solve the problem, we’ve got to get into the heads and the minds and the hearts of our young people, and it’s going to take all of us to do that.”

Detroit’s total of 411 homicides in 2012, up from 377 the previous year, includes 386 criminal homicides and 25 “justifiable homicides” that included three shootings by police, according to numbers released by the city. The number of criminal homicides increased 12 percent from 344 in 2011. The total in 2010 was 308.

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Even as violent crime rates in the U.S. fell for the fifth consecutive year in 2011, the homicide rate in Detroit rose to a level higher than nearly 40 years ago when the city was known as the Murder Capital, the Detroit News reported. The same day the city's official crime statistics were announced, a Detroit woman was charged with fatally stabbing her 8-year-old daughter and a cab driver was killed in a double shooting on the city’s northwest side.

“I think the message that we want our citizens to understand is that we need them. We need them to help us. I just don’t believe that our police department should have the total responsibility for safety in the city," Bing said. "There are, as the chief said, he can have an additional thousand cops, but there are things that are happening in homes and families in the communities and the neighborhoods that whether a cop was there or not is not going to stop the crime.”

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Homicides have declined nationwide for years, most notably in New York, where in 2012 there were 414 homicides and a rate of one per 19,915 people.

New Orleans reported a small drop from 199 to 193 in 2012. With a population 360,740, the rate was one per 1,869 residents.

In Washington, D.C., there were 88 homicides in 2012, the lowest total since 1961. With a population of 617,966, that puts the rate at one per 7,023 people.

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Elsewhere across the country, homicide rates made only slight jumps compared to Detroit.

In Los Angeles, the homicide rate increased from 291 to 294 last year, with a population of nearly 3.8 million.

The homicide rate in Chicago went up nearly 17 percent in 2012, topping 500 for the first time in four years. Last year’s total was 505, up from 433 in 2011.

Homicides in Cleveland, Ohio, spiked in 2012 with 97 and a rate of one per 4,060 people.

Philadelphia homicides increased from 324 to 331 in 2012. With a population of 1.54 million, that amounts to one per 4,642.

In St. Louis, which has a population of 318,169 people, the rate stayed the same at between 2011 and 2012 at one per 2,815 people. There were 113 homicides last year, well below the average of 141 for the five previous years.

Detroit Police Chief Logan said the criminal activity in the city comes from a small minority of the city's population.

"These aren't the average citizens we are talking about," Logan said. "Many of these people are involved in nefarious walks of life, and there's a difference between a law-abiding citizen who shoots a gun and a criminal or a thug who's out there using one."

Still, Mayor Bing offered messages of hope for the city.

“We can’t give up, we can’t give in, and we’ve really got to let the small percentage of our population that’s creating havoc in our city know that we’re not going to continue to accept it and all of us need to get involved and help each other solve the problem,” Bing said.

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