A team of three robbers stole suitcases holding 420 million yen in cash on a busy street in central Tokyo, police and media said on Friday, a rare crime in the Japanese metropolis that prides itself on safety.

The heist saw the thieves deploy pepper spray to grab luggage containing the money at around 9.30pm on Thursday near Ueno Station, an area popular with tourists, a spokeswoman at the Tokyo Metropolitan Police said.

She declined to give further details, but local media said the victims were a group of five Chinese and Japanese nationals who were trying to put suitcases containing the cash in a vehicle.

It was not immediately clear why the group was carrying the money.

Fuji Television said the victims told investigators that the cash was being delivered to currency exchange stations.

Separately, a man with 190 million yen in cash was also attacked with pepper spray by a group of three men in the early hours of Friday morning at a parking garage at Tokyo's Haneda Airport, local media said.

Police were investigating the link between the two attacks, broadcaster TBS said. (AFP)