Image copyright NurPhoto/Getty Image caption Authorities say police have been told to act with force if resistance is met

Indonesian police have fatally shot dozens of "petty criminals" in the lead up the 2018 Asian Games, rights group Amnesty International says.

The group condemned the deaths, calling for an investigation into the "shoot first and ask questions later policy".

At least 77 people have reportedly been shot dead since January, Amnesty said, with 31 deaths in police raids meant to clean up host cities for the Games.

Authorities have said that people were shot after resisting the police.

The raids began in July with high-ranking officials telling their officers "don't hesitate to take firm action", the BBC's Indonesian service reported.

The two-week-long Asian Games, which starts on Saturday, will take place in the capital Jakarta and the South Sumatran city of Palembang.

Authorities are deploying 100,000 police and soldiers for the 18th annual event, which will see some 17,000 athletes compete between 18 August and 2 September in the largest multi-sporting event outside of the Olympics.

"The authorities promised to improve security for all. Instead, we have seen the police shooting and killing dozens of people with almost zero accountability for the deaths," head of Amnesty Indonesia, Usman Hamid, said.

"The hosting of an international sporting event must not come at the price of abandoning human rights."

Image copyright Getty Images Image caption More than 100,000 police and soldiers have been deployed to protect the Games, which start Saturday

The killings peaked in the first half of July, when 11 people were shot dead in greater Jakarta and 41 others shot in the legs.

The total number of those killed and accused of petty crimes in 2018 represents a 64% increase on the same period in 2017.

"These shocking figures reveal a clear pattern of unnecessary and excessive force by the police," Mr Hamid said in a statement.

Thousands of people have been arrested and hundreds detained in an effort to ensure the safety of visiting tourists, according National Police Chief General Tito Karnavian.

Image copyright NurPhoto/Getty Image caption Some 5,000 have been arrested, and more than 700 charged with a criminal offence in the crackdown, Amnesty said

"In the last month... I have ordered my personnel to finish off all networks of pick-pockets and bag-snatchers," he told reporters in late July.

"If [criminals] fight back, don't hesitate. Finish them off," General Karnavian said.

The police operation is expected to end with the Games, but many people on the streets of Jakarta would not be opposed to the drive continuing, BBC Indonesian's Heyder Affan reports.

"I agree with the police action because it's [otherwise] very dangerous for the people," said one resident in the capital's old town.