Gardai fear a hitman linked to murdered Keith Branigan will avenge his killing after publicly threatening rival gang members.
Officers in Louth are braced for a backlash following the first murder in the Drogheda feud.
Branigan (29), a mid-level member of the crime group feuding with associates of Owen Maguire (35), was shot dead outside a caravan park in Clogherhead on Tuesday afternoon.
Within hours of the murder, a young criminal suspected of a previous feud murder attempt was publicly threatening associates of Maguire.
The hitman, linked to the gun attack on Owen's brother Brendan in February, approached a number of rival criminals and "was making all sorts of threats".
"He was furious. It was fairly soon after the gun attack and he was threatening associates of the Maguires," a source said.
"This individual is considered a dangerous criminal and there is an obvious concern that he'll follow up on those threats."
Local gardai are aware of the stand-off but it ended without incident and the young thug eventually left the scene.
Officers now fear a significant escalation in the feuding which has already seen five attempted murders and dozens of petrol bomb attacks.
Senior investigators said they would continue to deploy armed units across Drogheda as part of anti-gang Operation Stratus.
Superintendent Andrew Watters also moved to reassure the community that "everything is being done" by gardai to stop the violence.
"We have an operation in place in the Drogheda district to deal with serious organised crime and I would like to reassure the public that we have made a number of very serious detections, arrests, prosecutions," he told reporters at a press briefing yesterday.
"Everything is being done by An Garda Siochana in terms of resources, equipment and IT.
"Everything is being done both locally and nationally to attempt to protect the people of Drogheda and the surrounding areas."
The senior officer made an appeal for information over Branigan's cold-blooded murder, which he described as "indiscriminate and callous".
He said at least two people were involved and expressed his condolences to the victim's family.
"This was a particularly indiscriminate and callous act carried out in a very busy caravan park," Supt Watters said.
"There were a lot of families, women with young children in particular, close to the area of the shooting. Indeed some of these children were enjoying the last days of their summer holidays."
He said gardai had established that a red Lexus with the registration 05C24473 entered the caravan park and a gunman got out of the car.
He then opened fire at Branigan, with a number of stray shots also hitting two parked cars nearby.
Gardai believe that the gunman then fired another volley of four shots at Branigan who was caught in between two pieces of decking that he was working on.
The hit team then fled in the car toward Termonfeckin, and the Lexus was found burnt out on Thurles Road in the Whiteriver area of Dunleer.
The suspects then escaped in a black Toyota Avensis, registration WH 8024, which was later found burnt out in the Clonmore estate in Ardee.
Gardai are investigating if the Lexus was bought on a 'buy and sell' website, rather than being stolen.
Branigan was considered a mid-level member of the Drogheda crime gang involved in the feud with a Traveller mob linked to Owen Maguire, who himself was shot and seriously injured in July of last year.
Originally from Ballsgrove in Drogheda, Branigan had a number of convictions including for assault, burglary and criminal damage.
He was a close associate of the 24-year-old leader of his gang, who was previously targeted in two murder bids as part of the ongoing feud.
In June the mob boss managed to drive himself to hospital after being shot in the chin and shoulder as he was sitting in his car near Termon Abbey.