Two men have been arrested and 50-thousand euro worth of heroin seized in Limerick last night.

Gardai say the arrests were part of an investigation into organised crime in the city.

The men aged 40 and 43 were detained when armed gardai raided a house in St Mary's Park.

It's understood both are well known gangland figures.

They're being detained at Henry Street and Mayorstone Garda Stations and can be questioned for up to a week.