The mother of one of the young men is from Laois.
The families of two teenagers who died on a Leaving Cert holiday are said to be dealing with "immeasurable loss".
Andrew O'Donnell, who's mum is from Mountmellick, and Max Wall died in Greece in two separate incidents over the weekend.
The 18-year-olds were among almost 90 students from St. Michael's College in Dublin to visit the island of Ios.
The school is open to support students, while the Department of Foreign Affairs is providing consular assistance.
Chair of the board of Directors at the Spiritan Education Trust, Pat Kitterick, says he's thinking of those affected:
Youth Council Calls For Action As Most Young Adults Consider Emigration
Community Search For Missing Westmeath Man Seeks Sonar And Drone Equipment
ESB Acquires Offaly Solar Farm
Hauliers Fear Impact Of Rising Fuel Costs Ahead Of Budget
Midlands Enjoys September Sunshine As Warm Weather Set To Continue
Volunteers Asked To Join Search For Missing Midlands Man
Gardai Investigating Stand Off In Midlands Housing Estate
Five New Members Appointed To TUS Governing Body