Taoiseach Enda Kenny has today comdemned today's attacks across Europe and in Turkey.
Nine people were killed and dozens were injured, several critically, when the truck crashed into a busy Christmas market in Berlin tonight.
A gunman injured several people at a mosque in Switzerland's largest city, Zurich.
Russia's ambassador to Turkey Andrei Karlov was shot dead at a photo exhibition in Ankara, Turkey.
"On behalf of the Irish Government, I extend my condolences to the families of those killed in tonight's barbaric attack on the Christmas market in Berlin," said Mr Kenny.
"Our thoughts are with those injured and their families. Any Irish citizens with concerns should phone (+353) 1 4082000."
He continued: "I condemn the callous murder of Russia's Ambassador to Turkey and offer condolences to Ambassador Karlov's family.
"I condemn the cowardly attack on worshippers at prayer in Zurich this evening.
"These acts of violence have no place in society and constitute an attack on our fundamental values."
Minister for Foreign Affairs Charlie Flanagan said he is horrified by the loss of life in Berlin.
He stated that Ireland stands in solidarity with Germany, and has urged Irish citizens in Berlin to follow the advice of local authorities, and to make contact with their families who may be concerned.