GARDAI are on high alert ahead of the release from prison this week of a gangland criminal who is classified as extremely dangerous.
Ballymun man Derek 'Bottler' Devoy (35) is due to be released from Mountjoy Prison on Thursday after spending most of the past decade behind bars.
Sources say there are serious concerns that Devoy may try to avenge the murder of his older brother Michael 'Mad Mickey' Devoy (41), who was shot dead in Tallaght in January last year, or that he may become a target for the same mob that murdered Mickey.
Devoy will be closely monitored after his release, with gang tensions expected to escalate with him back on the streets.
In 2007, Devoy was jailed for seven years for the attempted armed robbery of a post office in Balbriggan a year earlier.
He was then given extra jail time in November 2007 for the non-fatal drive-by shooting at two of his neighbours in Ballymun in September 2005.
Devoy had many serious disciplinary issues in jail, particularly between 2006 and 2009.
At one stage in 2009, he was even transferred to a segregation area of high-security Portlaoise Prison.
Devoy has more than two dozen convictions to his name and is an associate of the two main suspects in the killings of Martin 'Marlo' Hyland and innocent young plumber Anthony Campbell.
He also has close links with other Ballymun criminals and the Finglas gang suspected of the gun murder of Tallaght criminal Carl Wynne in the summer of 2013.
"He is a very dangerous and volatile criminal," a source said.
Devoy was said to be extremely distraught at the murder of his brother.
He was not allowed temporary release from Mountjoy to attend the funeral last year because of concerns of further bloodshed if he was let out.