The government said the murder rate for the first three months the year has dropped 44 percent compared to a year ago, with 238 murders compared to 426 during the same period in 2010, the Jamaica Gleaner reported.
Jamaica's murder rate is one the highest in the world and officials said they've been able to lower it by concentrating police and military units in the most crime-infested areas.
But the human rights group Jamaicans for Justice said abuses by security forces and extra-judicial killings have increased since the crackdown started.
Glenmore Hinds, deputy commissioner in charge of criminal operations, said Jamaica has changed its methods to reduce the number of homicides.
He said police identified 46 significant criminal gangs operating across the island.
"I am not saying that we have dismantled these gangs but we are saying that significant progress has been made," Hinds told reporters at a media briefing Thursday.
Jamaicans for Justice said more than 400 civilians were killed in security operations in 2010 compared to 253 in 2009.
It said a "heavy-handed" approach resulted in "an alienation of the populace and an even more difficult environment for fighting crime."
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