Katsuya Takahashi, the last suspect implicated in the 1995 Tokyo Sarin gas attacks has been arrested south of the city.
A massive manhunt was mobilised in recent weeks after Takahashi fled his home.
The 54-year-old is wanted for his involvement in the Aum Shinrikyo cult and is suspected of driving a member of the group to a train station, where deadly gas was later released.
The gas attacks killed a total of 13 people and left 6,000 injured.
Tokyo resident Ryoichi Kawashima said the arrest came as a huge relief.
He said: "Everyone was unsettled and there were times when you would be scared to ride the trains. We can finally ride the trains in peace and I think everyone in Japan feels safe now."
Takahashi's arrest rounds up a trio of fugitives, including Naoko Kikuchi and Makoto Hirata who were both arrested earlier this year.