The Independent Monitoring Commission has blamed the Provisional IRA for the Northern Bank robbery in Belfast last December in its latest report.
The report also says certain unnamed senior Sinn Féin members, who are also Provisional IRA members, sanctioned the £26.5 million robbery and a series of other robberies across Northern Ireland.
"We believe that the Northern Bank robbery and abductions - and the other robberies and abductions - were carried out with the prior knowledge and authorisation of the leadership of PIRA," the report states.
"In our view Sinn Féin must bear its share of responsibility for all of the incidents," the IMC said. "
IMC report
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The IMC also claimed Sinn Féin could not be regarded as "committed to non-violence and exclusively peaceful and democratic means so long as its links to PIRA remain as they are and PIRA continues to be engaged in violence and other crime."
It called on the Sinn Féin leadership to choose between association with criminality and democratic means.
The IRA has denied any responsibility for the raid and, last week, it withdrew its offer of complete decommissioning. Sinn Féin does not recognise the IMC and say it was constituted outside of the terms of the Belfast Agreement.
Other incidents blamed on the IRA were a raid on a cash-and-carry in Dunmurry last May in which goods worth £1 million were stolen; the abduction of a number of people and robbery of a supermarket in Strabane in September and a kidnapping and robbery in Belfast in October, in which cigarettes worth £2 million were stolen from a delivery lorry.
The report said violence or the threat of violence was involved in all these incidents.
The four-strong independent body - headed by former Alliance Party leader Lord John Alderdice - also said it did not believe Sinn Féin had used its influence with the IRA to prevent this criminality.
It recommended the Northern Ireland Secretary of State, Mr Paul Murphy, use his powers to impose financial sanctions against the party, despite the fact that "if financial penalties are imposed Sinn Féin will try to benefit from that by portraying themselves as victims."
The IMC report added that Sinn Féin could have been excluded from holding ministerial office as a result of IRA criminality had the Stormont Assembly and Executive not been suspended.
The IMC report was released simultaneously in Dublin, London and Belfast.