Baton Rouge experienced a 4.7 percent increase in the number of murders in 2012 from 2011, according to preliminary statistics released Tuesday by the Police Department.

According to unofficial statistics, there were 67 homicides within Baton Rouge city limits in 2012, up from 64 in 2011, police spokesman Lt. Don Kelly said.

That number is down from 69 homicides in 2010 and 75 in 2009, according to crime statistics on the police department’s website.

Kelly said those numbers could change between Tuesday and when the department releases its official numbers to the FBI.

Kelly noted that in the first eight months of 2012, there was an average of more than seven murders a month and that number decreased to 2.5 murders a month in the final four months.

While the numbers are unofficial, Kelly said it is fair to conclude that there are several reasons — like targeted-enforcement efforts in high-crime areas, aggressively going after drug dealers, seizing numerous illegal weapons and arresting and booking misdewmeanor violators — that the homicide numbers have decreased during the final four months of 2012.

“There’s never one single reason that murders go up or down in a given time frame. They’re driven by all sorts of various factors, some of which law enforcement can affect, many that are beyond our ability to influence,” Kelly said in an email.

The East Baton Rouge Parish Sheriff’s Office, which investigates homicides that occur in the rural areas of the parish, has not released its numbers, but spokeswoman Casey Rayborn Hicks said they should be released later this week or early next week.

Baker Police Chief Mike Knaps said there was one homicide in the Baker city limits in 2012 and Zachary Police Chief David McDavid said there were none in the Zachary city limits in 2012.

East Baton Rouge Parish has witnessed an increase in the number of killings since 2005, with a peak in 2009 when 88 people were killed, 75 within the city limits of Baton Rouge. That increase followed a time in the late 1990s and early 2000s when there was a decrease in the number of killings in the parish.