The two foreigners had allegedly conspired to carry out blasts at a US consulate and an Israeli embassy.
The National Investigation Agency (NIA) on Wednesday arrested an accused, who had been on the run after jumping bail, in an espionage case involving a Sri Lankan and a Pakistani national.
Nuruddin alias Rafi, who was carrying a cash reward of Rs 5 lakh, was caught from the Rajiv Nagar area of Mysuru, Karnataka by an NIA team, an official statement said.
Following his arrest, a house search was also conducted and several "incriminating materials", including mobile phones, laptop, pen drives and a drone, were recovered, the agency said.
A non-bailable warrant was issued earlier against Nuruddin when he had failed to appear before the NIA Special Court, Chennai, after being released on bail under stringent conditions in August 2023.
The court had declared him a proclaimed offender on May 7 this year.
The case relates to a terror conspiracy by Sri Lankan national Muhammed Sakir Hussain and Amir Zubair Siddique, a Pakistani national employed at the Pakistan High Commission in Colombo, Sri Lanka.
They had conspired to carry out explosions at the US Consulate in Chennai and Israel Embassy in Bengaluru in 2014, the NIA claimed.
NIA investigations have revealed that Nuruddin was involved in financing the anti-national espionage activities through high-quality fake Indian currency notes at the behest of the accused Pakistani national.
The trial against Nuruddin, which was stalled after he had absconded, will now resume, the probe agency added.