"The situation is urgent," Blanco said. "Things like this should never happen, and I am going to do all I can to stop it."
The governor did not specify how many troops and officers she planned to deploy. Earlier Monday, Mayor Ray Nagin asked for as many as 300 National Guardsmen and 60 state police officers.
It was the first time the National Guard has been used for law enforcement in the United States since the immediate aftermath of Hurricane Katrina.
after five teenagers in an SUV were shot and killed in the city's deadliest attack in at least 11 years. Police said the attack was apparently motivated by drugs or revenge. Also, a man was stabbed to death Sunday night in an argument over beer.
"Today is a day when New Orleanians are stepping up. We've had enough," Nagin said. "This is our line in the sand. We're saying we're not going any further."
Nagin said he would not allow criminals to take over when the city is still trying to recover from the hurricane. The mayor said troops should be posted in heavily flooded neighborhoods to free police to concentrate on hot spots elsewhere.
Community leaders have raised fears that the violence could discourage people from moving back to New Orleans.
The National Guard had as many as 15,000 soldiers in the city in the weeks after Katrina. As many as 2,000 stayed until February, said Louisiana National Guard spokesman Lt. Col. Pete Schneider.
CBS News' Cami McCormick reports Blanco said plans were being crafted last week to step up anti-crime efforts, but the weekend slayings forced authorities to move faster. She said she was talking with New Orleans Police Chief Warren Riley about his exact needs.
Riley welcomed the support because the ranks of his department are depleted. The police force has about 1,375 officers now, compared with about 1,750 officers before Katrina. The population of 465,000 has rebounded to about half its size before the storm. "We know this is going to be a long, hot summer," Riley said.
The governor urged the mayor to put a juvenile curfew in place.
"I have two warnings: First, to parents, keep your teenagers off the streets and out of trouble. Second, to judges, I am urging you to keep hardened criminals where they belong — in jail and off the streets. We must protect our citizens."
Nagin's request for help had been backed by the City Council.
"If we don't have wind knocking us down, we have shooters knocking us down, and that's unacceptable," said City Council President Oliver Thomas.
Reaction to the mayor's request was mixed.
"As we tell people to come home, we have to keep these areas safe," said LaToya Cantrell, president of the Broadmoor Improvement Association, a heavily flooded neighborhood. "It's long overdue. Neighborhoods should not have been left alone to begin with. Pulling out was a mistake."
But Sherman Copelin, president of the New Orleans East Business Association, cautioned that handing over some neighborhoods to troops unfamiliar with those areas could be a mistake, saying officials should not "let someone come in and be a housekeeper."
The killings over the weekend brought this year's murder toll to 53, raising fears that violence was back on the rise in a city that was plagued by violent crime before Katrina drove out much of the population last year.
Crime has been creeping back into the city: 17 killings in the first three months of 2006, and 36 since the start of April.
At least three other people, ages 16 to 27, have been fatally shot in the same area where the five teenagers were killed early Saturday.
In addition to Nagin's request for troops and state police, the City Council said it would consider increasing overtime for police to put more officers on the street. It also called for a "crime summit" within two weeks.
"We have to deal with it now," Councilman Arnold Fielkow said. "If we don't make people feel safe in their homes, nothing will happen. Let's make this priority No. 1."