Amnesty International has condemned what it described as an alarming number of police killings of suspected drug dealers in Indonesia.

The rights group said on Wednesday that police had killed at least 60 suspects this year, compared to 18 in all of 2016.

The group warned that Indonesian authorities could be looking to emulate the "war on drugs" in the Philippines, in which thousands have been killed.

"This shocking escalation in unlawful killings by the police sounds serious alarms bells," said Usman Hamid, Amnesty's Indonesia director.

The group said it had collected data of the killings.

Shooting people on sight is not only unlawful, said Hamid, "it will also do nothing to address the root causes that lead to drug use in the first place".

OPINION: Why Jokowi's war on drugs is doing more harm than good

Indonesia's President Joko Widodo in July ordered police to shoot suspected drug dealers if they resisted arrest, saying "there should be no mercy".

His remarks drew comparison to those made by Philippines President Rodrigo Duterte, whose controversial crackdown on drugs has left more than 3,000 dead over the course of a year.

The killings in the Philippines may amount to "extrajudicial executions", Amnesty International said.

The rights group accused the police of resembling a criminal enterprise, killing mainly poor people suspected of being drug users or sellers, or paying others to kill them.

"Duterte should not under any circumstances be considered a role model for Indonesia," Usman said.

Of those killed in Indonesia in 2017, at least eight were foreigners, including three Chinese men.

Police said the suspects were shot because they resisted arrest, but no independent investigations were conducted, according to Amnesty International.

Indonesia has tough laws against drugs.

Since Widodo took office in 2014, Indonesia has executed 18 people for drug trafficking, defying international calls for mercy.