Gardaí are continuing to investigate the circumstances of the collision at Gormanston in Co Meath yesterday.
The collision involving three vehicles, a Bus Éireann bus, a lorry and a car, happened on the R132 at around 6.30am.
The two men who died in the collision have been named locally as lorry driver Wesley O'Reilly from Skerries in Co Dublin, who was aged in his 40s, and bus driver Paul Conway from Tallanstown in Co Louth, who was aged in his 50s.
A woman and a teenage girl who were travelling together in the car were taken to hospital to be treated for serious injuries.
It is understood that they remain in a critical condition in hospital.
A number of other passengers on the bus were also taken to hospital with non-life threatening injuries.
Loss of two commercial drivers 'tragic' - Irish Road Haulage Association
The president of the Irish Road Haulage Association has expressed his "deepest sorrow at the tragic loss of two commercial drivers".
Ger Hyland said that "these devastating incidents remind us of the risks professional drivers face every day in their commitment to keeping the country moving".
He urged everyone in the sector to "rally around those affected with compassion and support".
Mr Hyland added that the "entire haulage community stands united in grief".
"We remember our colleague who died at this time and reaffirm our commitment to promoting road safety and wellbeing across the industry so that such tragedies become ever more rare," he said.
Labour TD for Louth Ged Nash expressed his condolences to the families of the two men.
He said the Gormanston area is "just a few short miles from Drogheda", and that the bus driver who was killed had been based in the local depot there and had worked with Bus Éireann for "many, many years".
"I want to express my deepest condolence to his family, to the family of the truck driver whose life was cut short, and to those who are recovering in hospital after this dreadful, dreadful accident," he said.
Colleague pays tribute to Wesley O'Reilly
Wesley O'Reilly, from Skerries in North County Dublin, worked with Flanagan Timber, a timber merchant based in Duleek County Meath.
Keith Caffrey of Flanagan Timber said that Wesley O'Reilly had worked as a driver for the company since August.
"We are deeply saddened at the loss of our colleague Wesley. Even though it was only a short period of time, he was dedicated to his role. He was a warm character and a gentleman".
Mr Caffrey said that Mr O'Reilly was a very professional driver who took his role seriously.
He offered his thoughts and condolences to the families of both men who died in the collision.
Gardaí in Ashbourne are leading the investigation into the circumstances of the crash and are continuing to appeal for witnesses.
