Police in Amsterdam have arrested four people, two of them Irish, and seized three firearms.
The four were arrested in Amsterdam last night.
One of the men is a senior figure in the Kinahan crime gang and a convicted drug dealer.
His home in Drimnagh in south Dublin was searched a number of times by gardaí investigating the activities of the gang.
The second man is from Inchicore in the city.
Gardaí are liaising with the Dutch police as part of the investigation.
Dutch police say a man who was being threatened with a firearm ran up to police on Rembrandt Square in the city.
The gunman escaped into a "catering business" on the square and multiple police units were called.
The main suspect was arrested inside along with three other men and three firearms were recovered. Two are aged 29, the others 23 and 37.
Two are from Ireland, the other two from the UK.
Dutch police said in a statement this afternoon that all suspects are to be arraigned and the investigation is continuing.