Homicide rates increased by 20 percent in 2015, The Washington Post reported Thursday.

The Post reported that there have been 64 homicides so far this year, as compared to 53 by the same time in 2014. There have been 14 homicides in the past 17 days.

D.C. Police Chief Cathy Lanier told The Post that detectives had not found any patterns in the homicides, but added that while overall violence has decreased in D.C., “the lethality of the violence is up.”

Lanier said the Metropolitan Police Department will increase targeted patrols, including a group of detectives targeting dealers of synthetic drugs.

Lanier and D.C. Mayor Muriel Bower said Thursday that the spike in homicides in the city is linked in part to the sale and use of synthetic drugs, according to WUSA 9.

“You will get lots of batches of it where it is much, much more potent, and when that happens you see these spikes in overdoses and violence,” Lanier said, according to WUSA 9.