Sean Lahman

@seanlahman

The number of murders in the city of Rochester rose by 19 percent last year, the biggest increase in six years. The 43 homicides in 2016 was the highest total since 2007. There were 36 homicides in 2015 and 35 in 2014.

Investigators have said there was no clear pattern to the violence, no single reason to explain the rise.

The deaths often came in bunches. Four people were found dead in an apartment house on Leighton Avenue in January. Two young men were shot to death on back-to-back nights in July, the scenes just blocks away from each other on North Clinton Avenue. On March 31, two people were murdered in separate incidents a few hours apart.

But there were also periods of relative calm. There had been only one murder in the city in the seven weeks before those March killings, and there would not be another one until Mid-May.

► SEARCH THE DATABASE: Homicides in Rochester since 2007

The rise in murders in Rochester comes at a time when the long term trend for violent crime has been steadily declining. A decade ago, the city saw 53 murders. In the early 1990s, the number was usually more than 60 each year.

While last year's numbers showed that the overall crime rate in Rochester was at a 25-year low, they also showed that violent crime was a growing problem.

The number of aggravated assaults was up 15 percent in 2015. The number of shooting victims was up 20 percent. Charges for menacing — threatening someone with a weapon — were up nearly 25 percent.

To be clear, these numbers do not reflect the explosion of violence that's occurring in cities like Chicago, which ended the year with 762 homicides, or Memphis, where murders increased from 161 to 228.

The number of homicides in other upstate cities also grew in 2016. Buffalo was up slightly, from 42 to 44. Syracuse rose from 23 to 30, making it the deadliest year in that city's history.

The unofficial count of homicides is based on information provided by the Rochester Police Department and is subject to change, as investigators gather more information and grand juries hear cases and decide whether to bring charges. RPD will likely release official totals for 2016 in March or April of 2017.

Police departments are required to report the number of criminal homicides and other serious crimes to the US Department of Justice each year. The Federal Bureau of Investigation compiles the data from nearly 18,000 law enforcement agencies to publish their annual Uniform Crime Report.

SLAHMAN@Gannett.com

Rochester crime rate at historic low

RPD aims to curb spike in violence