A mayor of a violent town in Colombia is using scientific techniques to curb crime in his city.

Rodrigo Guerrero is the mayor of Cali, Colombia, the third largest city, and is a graduate of epidemiology from Harvard, BBC reported.

He has successfully cut down the city's murder rate by applying the tools used in his field -- which involves finding patterns.

Epidemiology is a way to track patterns and cause and effect in relation to health issues.

He told BBC that he is using a method epidemiologists use when tracking an unknown disease, which is the same tool he used 20 years ago in office.

"We always assume there are multiple causes. The secret, then, is to identify the different risk factors in order to deal with them. And to keep evaluating the results," he told BBC.

An atypical approach from those used by crime investigators, as seen in TV shows, but it has worked alongside traditional approaches.

"I estimate that, by the end of the year, it will be 58 or 59 per 100,000 inhabitants," Guerrero told BBC. ""It still is a terrifying rate, but last year's was 81. And we're confident things will get better."

Guerrero returned to office less than two years ago, after 20 years away from the seat. His first term was from 1992 to 1994.

Prior to his first term in office, where he introduced this new application of an analytical method to crime, no one had thought of treating the violence as an epidemic.

And regarding the point of "multiple causes," most officials had assumed the violence was linked to drug cartels. The two Guerrero identified were drugs and alcohol, and a study was published that highlighted the findings.

The city's murder rate was 126 per 100,000 inhabitants in 1992, compared to less than half that number anticipated by the end of this year.

Bogota soon applied the same methodology, but Cali has not been doing so in his absence, he said.

"When I got re-elected mayor of Cali I promised to cut down the murder rate to 60 per 100,000. But that's already done, so my new goal is to bring it down to 45 or 40," Guerrero told BBC.