At least three people have been killed after a truck was driven into crowds of shoppers in Stockholm.
The lorry was then crashed into a department store.
The main railway station and subway have been closed over reports the suspect ran towards an underground station.
Sweden’s Prime Minister Stefan Lofven says everything points to an act of terrorism.
Irish people in Stockholm are being advised to stay in a safe place indoors.
The Irish Embassy in the city says its monitoring the ongoing situation.
Anyone with concerns is asked to contact the embassy locally or the Department of Foreign Affairs in Dublin.