LOUISVILLE, Ky. (WDRB) -- Sunday morning marked the beginning of a violent 24 hours in Metro Louisville. 

Four people were murdered. 

Since one shooting happened in Shively, LMPD homicide detectives are handling three of those cases. 

"These guys work hard," said Sgt. Donny Burbrink of LMPD's homicide Unit. "It doesn't matter if you gave them two cases a year or 12 cases a year, they're still gonna put forth the effort and try and solve that case." 

The case load has drastically increased this year.

Police say in late September of last year, there were 39 criminal homicides in Louisville. 

So far this year, detectives have investigated 64. 

"It has put a strain on them both physically and mentally and family wise," Burbrink told WDRB News. 

City leaders point to a nationwide trend. 

"When you take a look at violence in cities across the country right now, there's a real uptick in almost every city across the country right now in homicides," said Louisville Mayor Greg Fischer. "We're certainly seeing that here in Louisville. We're up about 40 percent year over year." 

Burbrink says the homicide unit hasn't added any new people to deal with the case load.

He says they have gotten help from officers who focus on violent crime out of the 9th Mobile Division, formally known as the Viper Unit. 

But Burbrink says it's going to take more than just police to stop the killing. 

"We can only do so much on our end," he said. "At some point in time, the community is going to have to step up and say, 'We're tired of this. Can we do something to help you all out?' And the answer is always going to be yes." 

The homicide unit is asking for tips -- even if they're anonymous -- to help them solve these crimes and bring some closure to the victims' families. 

Police say out of the criminal homicides from this year, just over 50 percent have been solved. 

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