The bungling Brazilian hit-team who were busted with a machine gun and sawn-off shotgun in Co Offaly this week travelled to the scene in their own private car from Dublin, the Herald can reveal.
The four men were still being questioned at Portlaoise and Tullamore Garda stations last night with senior sources saying it is "likely" they will be charged with firearms offences today.
The development comes as officers served GIM forms on at least three people who live in a house in the Tullamore area that officers think was to be targeted in the early hours of Wednesday morning.
A GIM form is a written warning given to a person who gardai believe is in imminent danger of being murdered.
Last night senior sources told the Herald that the arrest of the hit-team had increased tensions in a spiralling Traveller feud in the midlands town.
"This crowd was hired by one Traveller faction to target another Traveller faction so obviously the targets are aware of what has happened here and are expected to fight back," a senior source said.
"Investigations to date have established that this Brazilian crew are no criminal masterminds at all - it is not as if they were flown into the country or anything like that.
"These are fellas that previously worked in meat factories and as pizza delivery drivers in the State. Some of them have minor criminal convictions such as public order, driving and drugs offences.
"It has not yet been determined how they got involved in a Traveller feud in Co Offaly but the belief is they were hired for the job because of connections linked to their low level involvement in the drugs trade.
"Analysis of CCTV has shown that one of them even drove his own car all the way from Dublin to Clara before the arrest operation took place so they were always going to be caught," the source explained.
Detectives have not yet established how or where they obtained the sub-machine gun, sawn-off shotgun and ammunition or how much the Brazilians were due to be paid.
Sources say the weapons were loaded and ready for use and that gardai have given official security advice to at least three people who may have been targets.
Yesterday the Herald revealed that feud in the Co Offaly town that started over a €70 drugs debt has been spiralling out of control over the past month and has now escalated to the point where innocent children could be murdered.
It is understood that the arrested men are aged between their 20s and 40s and two have addresses in Dublin, another in Ballymahon, Co Longford, with the fourth man based in another midlands location.
One of the suspects is understood to have arranged to fly out of Ireland this week.
Heavily armed officers from the Garda Emergency Response Unit (ERU) swooped on the four suspects in a car and van in Clara on Wednesday morning.
They had been followed by undercover officers from Dublin after local gardai enlisted the force's secretive Crime and Security branch who deployed the heavily armed Emergency Response Unit (ERU)
It is understood that the van was to be driven just over 10 kilometres to Tullamore for the attack on the Traveller's home.
The Brazilian hit-team were then due to return to Clara to escape back to Dublin in the car but gardai were watching their every movement.