A man is due in court this morning following a robbery at a pharmacy in Dublin's Castleknock, during which a customer was assaulted.

An off duty garda noticed a man acting suspiciously around a pharmacy in Castleknock shopping centre at around 7.25pm yesterday evening.

The man entered the pharmacy, threatened staff, demanded money and assaulted a customer.

The off duty garda entered the pharmacy and was joined by two uniformed Gardai from Blanchardstown, who he had alerted.

The man, in his 40s, was detained and brought to Blanchardstown Garda station.

He is due in court in Blanchardstown.

The customer was not badly hurt.