Labour's Alan Kelly said he asked Garda Commissioner Drew Harris at the Oireachtas Justice Committee about the investigation leading up to that arrest.
A Dail committee has heard Gardaí engaged in a 'controlled delivery' of arms to Evan Fitzgerald, the man who died in the shopping centre shooting in Carlow earlier this month.
The 22-year-old from Kiltegan in County Wicklow was out on bail at the time, after being arrested last year near Straffan for possession of firearms.
Labour's Alan Kelly said he asked Garda Commissioner Drew Harris at the Oireachtas Justice Committee about the investigation leading up to that arrest - and how the guns had come into his possession.
Garda Commissioner Drew Harris said controlled delivery is used for both organised crime and "for our terrorist defence".
He said controlled delivery is "very sensitive police methodology".

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