Since assuming office in January, 2008, Mayor Michael Nutter has tried various strategies to combat violent crime.

Elected partly for his tough stance on crime, Nutter’s crime-fighting efforts include stop-and-frisk, new curfews for youth and increased community policing.

There has been some success. The curfews laws and increased police presence appeared to have halted so-called flash mobs of young people attacking shoppers in Center City.

Overall violent crime was down in Nutter’s first term.

But just a month in his second term the mayor is now facing a troubling increase in homicides, with 31 murders so far this year compared to 25 at the same point in 2011 — an increase of nearly 25 percent.

Frustrated by the spike in murders so far this year, last week the mayor announced a new set of crime fighting initiatives.

Nutter said the city will now offer rewards of up to $20,000 for information leading to a conviction in a homicide and rewards of $500 for information leading to the recovery of an illegal weapon.

“To every criminal out there, I just put a $20,000 bounty on your head,” said Nutter during a news conference.

Only time will tell if the bounties will be effective and how long the city can afford to offer them.

It is also not known if $20,000 will be enough for witnesses to come forward when faced with possible intimidation by violent thugs.

The mayor declined to estimate what the cost of the program might be, but said last year’s city budget had a $500,000 reward fund. Council President Darrell Clarke said the new initiative would be costly but he supported it.

The city may need private donors to step up to help maintain the reward fund.

But money may not be enough. Potential witnesses need to know they will be protected if they provide information to police.

What we hope is that the new initiatives will send a strong message to criminals that the city will try every means to bring them to justice.

Police Commissioner Charles Ramsey emphasized the importance of good tips and information in helping makes arrests.

“We need information to be able to get these people off the streets,”

We know offering rewards can make a difference in combating crime.

The mayor announced the new initiative less than a week after reward money helped lead to the arrests of three men in the fatal beating of a recent college graduate who had been trying to hail a cab in the city’s historic district.