In pictures: Philippines President Rodrigo Duterte's past as the gun-toting mayor of Davao City

As Rodrigo Duterte was sworn in as the Philippines' 16th president on 30 June 2016, he delivered a speech – one hand on the Bible – in which he promised a "relentless" and "sustained" fight against corruption, criminality and illegal drugs. He conceded that many believe his methods "are unorthodox and verge on the illegal" – however, he said he knew right from wrong and would abide by the rule of law.

Duterte was previously mayor of the city of Davao, where, according to human-rights groups, death squads have killed at least 1,400 people since 1998, most of them drug dealers, addicts, petty criminals and street children. Duterte denies any involvement in vigilante killings.

In February 2017, Arturo Lascanas, a retired policeman, testified before a Senate hearing that he killed around 200 people under Rodrigo Duterte's orders when he was the mayor of Davao City.

In December 2016 Duterte told a gathering of businessmen that as mayor of Davao City he "personally" killed criminals as he prowled the streets. He later admitted killing three men involved in a kidnapping case during a police gunfight in the late 1980s – although he further clarified that he was unsure whether the bullets from his M16 rifle killed the suspects.

The brash-talking president suggested that he used to roam around his sprawling city as mayor on a big motorcycle to look for criminals to kill so policemen would emulate him. "In Davao, I used to do it personally. Just to show to the guys that, if I can do it, why can't you?" Duterte said. "I go around in Davao with a motorcycle, with a big bike around, and I would just patrol the streets looking for trouble. I was really looking for an encounter to be able to kill."

Justice Secretary Vitaliano Aguirre II has defended Duterte, saying the president often exaggerates killings of criminals to send a chilling warning to lawbreakers. The photos in this gallery show Duterte handling machine guns in the 1980s and 1990s.

Duterte has also revealed that he once threw a suspected kidnapper out of a moving helicopter when he was mayor of Davao City. After visiting areas affected by Typhoon Nina, Duterte gave a speech at the Camarines Sur provincial capital, during which he elaborated on his plans to crackdown on corruption within the government. "If you are corrupt I will fetch you with a helicopter and I will throw you out on the way to Manila," he said. "I have done that before, why should I not do it again?"

The former crime-busting mayor of the southern city of Davao had said that the war on drugs would be over within six months but has since pushed back the deadline. He has said that he will continue "until the last pusher drops dead".