They were arrested following police raids on the loyalist Shankill Road in west Belfast.
The raids were conducted by the team of detectives led by the new Metropolitan Police Commissioner John Stevens.
That team was invited to Belfast by the RUC Chief Constable Sir Ronnie Flanagan to take a fresh look at the killing amid a new wave of accusations of security force collusion in the murder.
The Stevens team charged one man, William Stobie, with the murder in June.
Mr Stobie, a self-confessed police informer and Ulster Defence Association (UDA) quartermaster, was recently released on bail while he awaits trial.
He was at the centre of a series of court hearings when the Stevens team tried and failed to force a Belfast journalist to hand over the original notes of an interview with Stobie - carried out nine years ago but only published after he was arrested and charged.
![[ image: width=150]](/olmedia/500000/images/_503700_stobie-150.jpg)
The defendant has denied murdering Mr Finucane, but admitted he supplied a gun and disposed of it afterwards.
He claimed when he first appeared in court charged with the killing that he had informed his police handlers that a person was to be murdered on the night Mr Finucane was shot dead in front of his family at his north Belfast home, but that he did not know the target.
The UDA's political allies in the Ulster Democratic Party (UDP) have condemned the latest arrests and accused the Stevens team of deliberately harassing loyalists.
UDP spokesman John White said: "I can only describe the arrest and detention of these three men as part of an ongoing campaign of police harassment being directed at loyalists living in the greater Shankill area."
He said while he had no difficulties with genuine investigations into serious crime, the arrests were "clearly only of a cosmetic nature designed merely to placate republicanism".
Mr White said he had lodged a formal complaint with the local RUC and called on the Stevens team to release the men immediately and to "discontinue the cosmetic and disruptive charade surrounding the so-called investigation of this murder."
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