Ireland is "frozen in shock" after authorities named six students who plunged to their deaths when a balcony collapsed during a 21st birthday party in the US.
A number of them were from south Dublin and students at the city's University College Dublin and had gone to Berkeley, California, to start a dream trip on popular summer working holiday visas.
They were named as Ashley Donohoe, 22, and Olivia Burke, Eoghan Culligan, Niccolai Schuster, Lorcan Miller and Eimear Walsh, who were all 21.
Ms Donohoe was an Irish-American from Rohnert Park, California, while the others had addresses in Ireland.
Mr Culligan was from Co Mayo.
They died from multiple blunt traumatic injuries, according to the coroner's bureau at Alameda County Sheriff's Office.
Another seven were seriously injured in the incident and remain in several hospitals around Berkeley.
In a twist of fate, local police had received a call to reports of noise from the apartment shortly after midnight local time, but diverted to an emergency after a reported shooting in the city was prioritised.
The balcony collapsed less than 45 minutes later.
Philip Grant, consul general with the Irish Department of Foreign Affairs in the region, said the tragedy touched everyone in Ireland.
"For many of my countrymen (the visa working holiday) is a formative experience and to have this happen at the start of this season is something that has left us all frozen in shock and disbelief," he said.
"We are a very close, tight-knit group. Ireland is a small country and when you have the numbers that we had here today, very few of us have been left untouched by this tragedy."
It is believed there were 13 Irish students on the fourth floor of an apartment complex in the college city shortly after midnight when it came apart from the building.
The collapse saw the victims plunge about 40ft to the ground.
The complex in Library Gardens off Kittredge Street was fully built in 2007.
City inspectors sealed off and "red-tagged" all the other balconies on the building an ordered the owner to carry out tests within 48 hours.
Many of the students who had been attending the party were past pupils of St Mary's College in Rathmines, south Dublin.
University College Dublin president Andrew Deeks sent a message of condolence to the family and friends of those who died.
"We cannot comprehend the desperate shock and grief they are feeling and we are heartbroken at their suffering and loss," he said.
"Our students, like thousands of others across Ireland, head to the US each summer on J1 visas to enjoy the experience.
"It is heartbreaking to imagine that such a tragedy would strike these wonderful students when their lives are opening up to discover the world."
The first relatives of those who died will arrive on the US west coast over the next few hours.
Addressing the parliament in Dublin, Ireland's Taoiseach Enda Kenny said: "My heart breaks for the parents who lost children this morning and I can only imagine the fear in the hearts of other parents whose children are in California this summer as they seek to contact them now."
Foreign Affairs Minister Charlie Flanagan said: "It's an appalling tragedy, an appalling loss of life for young people whose hopes and dreams of the future have suddenly and without notice been shattered."
Those caught up in the incident were rushed to hospitals and trauma centres in and around Berkeley, and also in Oakland and to Walnut Creek, with fire crews from several stations in the city involved in the emergency response.
Social workers were on hand in some of the hospitals to field calls from family and friends of those caught up in the accident while the University of California Berkeley also provided trauma counsellors.
Irish president Michael D Higgins added words of condolence while on a state visit to Italy.
"I have heard with the greatest sadness of the terrible loss of life of young Irish people and the critical injury of others in Berkeley, California, today," he said.
"My heart goes out to the families and loved ones of all those involved. I have been informed of the consular assistance being provided to assist all of the families involved and I have asked to be kept informed as further details emerge."
The US ambassador to Ireland, Kevin O'Malley, expressed sympathy to the families, loved ones and friends of those who died.
"All of us at the United States embassy are greatly saddened by news of this tragic incident and are ready to do whatever we can to assist the Irish Department of Foreign Affairs at this difficult time. We will continue to co-ordinate as more details become available," he said.
Northern Ireland Deputy First Minister Martin McGuinness added his condolences over the tragedy.
"Shocking news of the deaths of several young Irish people in a tragic accident in California. My heart and sympathy goes out to their families," he said.
Archbishop Eamon Martin, leader of the Catholic Church in Ireland, said he was praying for the families of victims during their "profoundly painful" time.
"Like many others, I am shocked and deeply saddened to hear the reports of the tragic deaths of five Irish students earlier today in Berkeley, California," he said.
"This devastating news will be felt by Irish people everywhere and particularly by those who have family and friends abroad."