Police in Japan were Monday mulling how to divide the $250,000 reward for information that led to the capture of the final suspects in the 1995 nerve gas attack on Tokyo's subway, reports said.
Police authorities and a group of retired investigators had put up two lots of 10 million yen ($125,000) for anyone who tipped them off over where they could find two of the country's most wanted fugitives.
Their 17-year hunt ended earlier this month with the capture at a cafe of Katsuya Takahashi, a 54-year-old believed to have been part of a gang that released Nazi-developed sarin on Tokyo's heaving underground system, killing 13 people and injuring thousands.
Local media reports have suggested two people are in line for the 10 million yen reward, one who called police to say a man who looked like Takahashi had been seen at the cafe two days earlier and someone who worked there.
Reports say it was only at the staff member's urging that officers even bothered to have a close look at the customer resembling the man whose image had been plastered across televisions and newspapers for the previous few weeks.
When they talked to the man -- who was about to leave -- he confessed his identity and was later arrested, reports said.
Takahashi's arrest came weeks after fellow fugitive Naoko Kikuchi, 40, was arrested following what local media have said was a tip off from a relative of her boyfriend.
Her lover, reportedly aware of her status as one of Japan's most wanted, was arrested on suspicion of harbouring a criminal suspect.
Police are reportedly studying whether the tipster qualifies for the 10 million yen bounty, which cannot be given to an accomplice or to someone who committed a different crime to receive the information, according to police.
Tokyo Metropolitan Police and the National Police Agency declined to immediately comment on the status of the rewards, which will be distributed after reviews by a police agency committee and the nation's police chief.
Neither Takahashi nor Kikuchi have yet been indicted, although both are expected to face murder charges eventually for their part in one of Japan's worst ever mass-killings.
Both have confessed to having been involved with Aum Supreme Truth, a doomsday cult led by a partially blind guru who had an obsession with sarin.
Thirteen of those convicted over the 1995 attack are on death row.