MANILA, Oct 20 (Reuters) - The Philippines will look into thousands of killings in President Rodrigo Duterte"s war on drugs, its justice minister said on Wednesday, after a review of a sample of cases indicated foul play in dozens of deadly police operations. Menardo Guevarra said his Department of Justice (DOJ) would expand its review to the more than 6,000 killings during police operations, after which many officers were cleared of wrongdoing in internal police investigations. "Time and resources permitting, the DOJ will review these thousands of other cases, too," Guevarra told Reuters. The decision indicates a shift from the Philippines" vehement defence of the drugs war, which has seen the government scold critics and activists who alleged there were systematic executions of drug suspects by police. The Philippines has come under pressure from the United Nations to hold a thorough probe and the International Criminal Court recently announced it would investigate the crackdown. The government, however, has said it will not cooperate because the Philippine justice system is functioning. Wednesday"s release of details of 52 drug war deaths marks a rare admission by the state that abuses may have taken place. In several of those, victims had no traces of gunpowder on their hands, or did not have a gun at all. The DOJ also said police had used excessive force, shot suspects at close range and relevant medical and police records were missing. The findings, which are subject to further case buildup and criminal charges, could challenge the government"s narrative of the war on drugs. LICENSE TO KILL Duterte has for five years defended police and argued that all those killed were drug dealers who resisted arrest. He has publicly said police could kill if they believed they were in danger and he would pardon any who end up in prison. Duterte"s office did not immediately respond to a request for comment on Wednesday. Police chief Guillermo Eleazar vowed no cover up. "We will make sure to hold accountable those who should be held accountable," he said in a statement. Carlos Conde, Senior Philippines Researcher at Human Rights Watch, said the war on drugs was about more than a few rogue police. He criticised what he called light punishment being recommended by police internal affairs, which included suspension, demotion or dismissal. "Based on these 52 cases alone, it is clear that the drug war is an illegal, murderous state policy being carried out by police force that has been commanded by the president himself to disregard due process," Conde said. One of the cases reviewed by the DOJ involved a suspect who was shot 15 times by police. The DOJ said there was no crime scene report or autopsy, nor were ballistics or paraffin tests carried out to determine if the suspect was armed. It said it was disclosing the findings so that families of victims could know deaths were being investigated, and to invite witnesses to come forward. More than 6,000 people have been killed by police in the crackdown, but activists say many thousands more drug users and peddlers were shot dead by mysterious gunmen. Police have denied involvement in those.