DUBLIN, Feb. 17 -- Irish police arrested seven people, including a member of the IRA-linked Sinn Fein party, and seized millions of dollars suspected of being stolen in the December robbery of $50 million from a Belfast bank, the biggest cash theft in British history, authorities said Thursday.
In the biggest of several coordinated raids targeting Irish Republican Army money-laundering operations, police said they recovered at least $4.4 million at a house in the village of Farran, 10 miles west of the city of Cork.
Police also seized about $155,000 at a property in the Douglas section of Cork City and arrested three men and a woman in other Cork-area raids.
Police said the operation began Wednesday night with the arrests of three men at Dublin's Heuston train station.
Detectives trailed a suspected major money launderer from Cork who, after stepping off the train in Dublin, was caught delivering a suitcase containing $122,000 in laundered euro notes to two men from Londonderry, Northern Ireland.
A team of more than 100 detectives had planned the raids for weeks in hopes of finding the $50 million stolen Dec. 20 from the main cash vault of Northern Bank in Belfast, police said.
Police could not immediately confirm whether any of the seized money was stolen from the Northern Bank. They said the $155,000 recovered in the Douglas raid consisted of Northern Bank-produced notes.
"This is a massive operation, and our top priority must be first and foremost to finish the searches at hand before we examine the cash itself in greater detail," one detective said on condition of anonymity.
Officers would not begin comparing serial numbers on the seized cash with the records provided by Northern Ireland police until at least Friday, he said. About two-thirds of the cash stolen from Northern Bank was in newly minted notes bearing the bank's distinctive design.
Forensic specialists first must comb the seized cash for possible fingerprint or other evidence, which could take weeks, he said.
If the cash recovered Thursday is from the Northern Bank, it would mark the first breakthrough since the robbery investigation began. Police chiefs in Ireland have blamed the outlawed IRA but failed to recover any of the cash or charge anyone in connection with the robbery before Thursday.
Police, in keeping with usual practice, refused to identify any of the arrested people by name. Under Irish law, all seven can be interrogated without charge until Friday night or Saturday morning.
Sinn Fein declined to make immediate comment. The party previously has stressed that it believes IRA denials of involvement in the robbery.
But the British and Irish governments and all other political parties in both parts of Ireland have blamed the IRA, which has been Ireland's most proficient robber of banks.