The body of physician Tetsu Nakamura, a devoted aid worker who was killed in a shooting four days earlier in Afghanistan, was brought back to Japan on Sunday by members of his family.

The 73-year-old Nakamura, who headed the Peshawar-kai aid group based in the city of Fukuoka, southwestern Japan, and five Afghans including his driver were killed Wednesday as armed men attacked their vehicle in Jalalabad in the eastern province of Nangarhar.

The airplane carrying the body arrived at Narita airport near Tokyo around 5:30 p.m. It will be taken to Fukuoka on Monday morning from Haneda airport.

Japanese police will conduct an autopsy to determine the cause of Nakamura's death. A funeral is scheduled for Wednesday in Fukuoka, the aid group said.

Nakamura's wife and oldest daughter as well as Senior Vice Foreign Minister Keisuke Suzuki laid flowers and observed a moment of silence as the coffin was unloaded at Narita airport.

The civilian plane left Kabul on Saturday after the Afghan government held a ceremony at the airport, with President Ashraf Ghani joining soldiers to carry the coffin. Ghani also met with the wife and daughter.

Authorities in Nangarhar have said they obtained information about a possible attack on Nakamura about a year ago and had assigned four bodyguards to protect him.

Anti-government militants, including the Taliban and Islamic State, operate in the province.

Shah Mahmood Miakhel, governor of the province, told reporters on Thursday there is evidence that the attack was planned outside of Afghanistan, without elaborating. Further investigations are necessary, he added.

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