The Philippines police chief announced the relaunch on Monday of anti-narcotics operations he hoped would be less bloody, "or even bloodless," entering a new phase in a war on drugs that has caused international alarm.

Addressing hundreds of officers, Philippine National Police (PNP) Chief Ronald dela Rosa said the PNP was reforming and called on "men of burning desire" to join a new task force, the Philippine Drugs Enforcement Group.

The PNP has been lambasted by human rights groups that allege extrajudicial killings are systematic in President Rodrigo Duterte's anti-drug campaign, in which more than 8,000 people have been killed since he took office last June.