A Sinn Féin assembly member questioned about an IRA atrocity that killed nine people yesterday accused police of ruining his reputation.
Francie Brolly, who was among three men and a woman arrested and released without charge by detectives investigating the 1972 Claudy bombing, denied any involvement in the attack.
The East Derry MLA claimed the only reason given for him being treated as a suspect was that he lived 10 miles from the scene of the blast.
"I'm really seething with anger. These people could have come to my house at any time if they wanted to see me about Claudy. The whole charade about the arrest reminded me of internment," Mr Brolly said.
He added: "This has harmed me personally and it has harmed my family. Apart from the political kind of undertones, it has been a character assassination."
Mr Brolly's home in Dungiven was raided by police on Tuesday during an operation that also involved three other arrests including that of a 58-year-old woman from Dungannon, Co Tyrone. These arrests follow on the reopening of the Claudy investigation arising from claims that the late Fr James Chesney was involved.
All four were freed on Wednesday night, although police said they were preparing a file to be sent to Northern Ireland's public prosecution service.
Mr Brolly, who was elected to the Northern Assembly in 2003, said the arrest had made him rethink his stance within Sinn Féin as one of those moving towards the party accepting that policing in Northern Ireland had changed for the better.
"They are not only investigating something that happened 33 years ago, but they are actually going back 33 years."
The only reason he could give for his arrest was that it was political motivated.
"Without going into any detail of how the interviews went, fundamentally, the only evidence, if you can call it that, they were putting forward for my possible knowledge of what happened in Claudy was that I live in Dungiven, which is 10 miles from Claudy. It was as ridiculous as that."
Mr Brolly, who has recorded albums and performed as a traditional music singing duo with his wife, Anne, a former mayor of Limavady, accepted that others may still harbour suspicions following his detention.