MANILA - The number of crimes committed in the Philippines dropped by 13 percent in 2016, according to records from the national police, showing a continuation of the downtrend in the last four years, and amid President Rodrigo Duterte's war on drugs which was launched last year.

Data obtained by Kyodo News from the Philippine National Police indicates that the total crime volume across the country fell from 675,816 recorded incidents in 2015 to 584,809 in 2016.

Nearly one-fifth of the total crime volume in the entire year was categorized as "index crimes," defined by the police as those that are "serious in nature and which occur with sufficient frequency and regularity such that they can serve as an index to the crime situation."

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Crimes in this category -- which includes homicide, murder, physical injury, rape, robbery and theft -- numbered 139,462 for 2016.

Meanwhile, "non-index crimes," or those that involve violations of special laws and ordinances, made up the remaining 445,347 instances.

Volunteers Against Crime and Corruption, a local crime watch group, believes Duterte's illegal drugs campaign has added much to the decline in the number of crimes in the last year.

"He has really shown the political will to curb the proliferation of illegal drugs and to really pin down drug suspects," Dante Jimenez, the group's founding chairman told Kyodo News, stating that that a large number of crimes in the country are borne out of drug addiction.

Jimenez suggested that legislators should also pass a proposed law in Congress reviving the death penalty in the country, as well as a bill lowering the age of criminal liability to deter would-be criminals.

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Crime rates have been dropping in the country in the last several years, according to the police, with the number of crimes recorded in 2013 and 2014 being 846,147 and 714,632, respectively.

This illustrates fluctuating annual rates of decline in the crime situation in the Philippines, a country with a population of a little more than a hundred million, with a decline of 16 percent from 2013 to 2014, and 5 percent from 2014 to 2015.

Police chief Ronald dela Rosa said last December that the decline in crimes in the first months of the Duterte administration was brought about by the government's campaign against illegal drugs.

Duterte, who took office last June, launched at the start of his term an all-out war against the illegal drug industry in the Philippines, with the police leading the campaign.

The president has pointed to the use of illegal drugs as a culprit in many of the crimes in the country, from petty murders and robberies to corrupting politicians and institutions, identifying it as a scourge that must be eliminated.

He ordered a stop to the involvement of the police in his drug war in the last week of January, after some officers were accused of abducting and murdering a South Korean businessman inside the compound of the police headquarters in Manila under the guise of anti-narcotic operations.

Duterte has since accused the police of being "rotten to the core," despite an earlier promise of shielding police them from legal prosecution in their killing of drug offenders under the campaign.

From July 2016 until the end of January 2017, more than 2,500 drug suspects have been killed in police operations, leading to much international criticism of Duterte's war on illegal drugs.

==Kyodo