It has emerged that police in Northern Ireland missed catching the gang responsible for Monday's £22 million robbery at the Northern Bank headquarters in Belfast by minutes.

Police were outside the Northern Bank headquarters just moments after a white van made off with the last of the robbers' £22 million pounds.

Meanwhile, the Provisional IRA has denied any involvement in the heist.

A senior republican source claimed: 'We are dismissing any suggestion or allegation that we were involved.'

The denial came after police refused to rule out paramilitary involvement in the heist.

It has emerged that the PSNI was told about men acting suspiciously outside the bank on Monday.

A traffic warden also reported seeing a white van parked in the vicinity. The PSNI has confirmed it received the report and that it had been acted on. 

However, police said it was not confirmed that the vehicle spotted by the warden was the same white box van used by the gang.

Earlier, Ian Paisley Jr of the DUP said he believed the robbery had all the hallmarks of Provisional IRA activity.

In a BBC interview, Mr Paisley, who is his party's delegate on the Northern Ireland Policing Board, said he believed the police could indicate quite quickly which paramilitary organisation was behind the raid.

Detectives are understood to have drawn up a shortlist of gangs capable of carrying out the robbery.  

They say half of the money stolen was made up of new notes with traceable serial numbers, making it virtually impossible to launder.

Officers are continuing to examine hundreds of hours of closed circuit television tape taken from the bank and neighbouring buildings.

They have also been interviewing at length the two bank officials who were abducted from their homes in west Belfast, and Co Down, prior to the robbery.

Over 50 officers are involved in the investigation.

The PSNI has renewed its appeal for information from the public about the robbery, and is asking anyone who was shopping in the vicinity of the bank on Monday evening to get in touch.