(This post has been updated)

According to information provided by the Philadelphia Police Department, there were six fatal hit and runs as of Thursday, up from four at the same time last year. That's a 50-percent increase.

Three of this year's victims were on foot, two were on bicycles and one was on a motorcycle, police said.

There have only been arrests in two of the six fatal hit and runs this year, police said.

Overall, there have been 17 fatal auto-pedestrian accidents in 2016, up from 11 at the same time last year. That's a 55-percent increase.

Nonfatal auto-pedestrian accidents with injuries are up 4 percent from 540 last year at this time to 560 this year. Nonfatal auto-pedestrian accidents without injuries are up 30 percent, from 117 at this time last year to 152 this year, police said.

The latest hit and run happened around 9:13 p.m. Wednesday when 18-year-old Kevin Maldonado was run down in the 3900 block of Old York Road in Hunting Park by a woman in a white floral dress who was driving a stolen white Prius.

Even though the driver probably saw Kevin get thrown in the air and slam into the road, she did not stop. Instead, police said she sped off, abandoned the car and ran away on foot.

Kevin, who suffered severe head trauma, was pronounced dead at 9:28 p.m. at Temple University Hospital. The woman who hit and killed him has yet to be caught.

What makes people run instead of stop and how do they live with themselves afterward?

I'll never forget a story I did back in 2011, about how - because of a loophole in state law - it actually behooved intoxicated drivers who hit someone to flee the scene. In cases of fatalities, if a DUI driver stayed on the scene, they faced a minimum sentence of three years in prison, but if they fled and were later apprehended, they only faced a one-year mandatory prison sentence.

I'll never forget the families of hit-and-run victims I interviewed for that story. How one mother was given an electric blanket for Christmas so she could keep warm as she sat with her daughter on cold nights - at the cemetery.

"Families of hit-and-run victims are given a life sentence," she told me.

But the legal loophole was closed in 2014 with Kevin's Law, which raised the mandatory minimum sentence for fleeing the scene of a fatal accident from one to three years, so it no longer benefits drunk and high driver's to leave the scene.

Unfortunately, the law change seems to have done little to ebb the unrelenting wave of hit and runs our city is facing this year. From the pastor who was hit and killed last week after he dropped off a group of recovering drug addicts to the warehouse worker who was killed by a hit-and-run driver as he waited at a bus shelter for his ride home, these are the victims of people who probably never intended to kill, but weren't human enough to stay.

Though hit and runs aren't considered homicides and don't count toward the city's murder tally each year, it's hard to see them as anything but callous killings. In all of last year, there were 13 fatal hit-and-run crashes that killed a total of 15 people.