It is understood Gary Hutch's family had been told his life was under threat weeks before his death.
Today Police in Spain are examining CCTV footage near where the Dublin criminal was fatally shot yesterday morning.
Gary Hutch was gunned down in an apartment complex near Marbella yesterday morning.
At about 11.30am yesterday morning Gary Hutch was ambushed by a masked man in the holiday resort of Miraflores near Marbella.
He was the nephew of former Dublin criminal Gerry "The Monk" Hutch.
The Irish Independent reports he was gunned down by an attacker wearing a balaclava, who escaped in a car which was later found abandoned.
It is understood paramedics tried to revive the 34-year-old, but he died at the scene.
Local Spanish police are investigating the killing.
Conor Feehan is chief reporter with The Herald. He told Newstalk Breakfast this could relate to a Dublin feud.