Tensions are rising as gangsters linked to Ryan turn on his associates.
Sources say that the Real IRA in Dublin is descending into chaos with members carrying out punishment shootings and issuing death threats.
The mob has split into factions as members engage in a power struggle.
Detectives now fear even more bloodshed after the kneecapping of one of Ryan’s best friends.
A source said: "It is a situation that could get messy. There has been a major blow-up among them. Some of them are blaming each other for informing to the gardai and there are a number of cash disputes going on within the faction as well.
"The murder of Alan Ryan left a power vacuum and there are a lot of tensions within the organisation."
Ryan's friend Nathan Kinsella (33) was abducted in Tallaght and shot twice in the leg with a handgun. Thugs drove him around in a van before carrying out the shooting.
He was then dumped at Le Fanu Road, Ballyfermot, at 12.10am yesterday.
Kinsella was recovering in hospital today where he told garda he did not know the shooter.
Just days before Kinsella -- who is from Matt Talbot Court in Dublin's north inner city -- was targeted, another pal of Ryan's was warned by gardai that there was an imminent threat against his life.
This man, a 32-year-old from Tallaght, who has previous convictions for firearms offences as well as being part of a lynch mob who attacked and abducted an innocent teenager, was given a formal warning by detectives last week and offered security advice. It is understood that the threat comes from dissident republicans.
Meanwhile Nathan Kinsella has not made a formal complaint to gardai about the weekend incident.
Gardai have been working on the theory that he was targeted by Real IRA associates.
The terror group, which now calls itself simply 'The IRA', has expelled dozens of members and stood down certain active service units in a purge against suspected informers.
Command has been transferred to hardliners in Northern Ireland and many of Alan Ryan's close pals have become "unwanted persons".
Detectives are probing whether the weekend gun attack on Nathan Kinsella was ordered in the North.
Kinsella was charged with IRA membership in the Special Criminal Court in September as part of the massive investigation into paramilitary criminal activity at the funeral of Alan Ryan in which shots were fired over Ryan's coffin.
He is due to appear in court again on December 11.