A total of six persons were injured when a four-wheel drive vehicle with nine persons on board met with the accident on Thursday near Samad Al Shams in Ibra, about 140 km from Muscat, The Oman Times reported.
Sunil Kumar Tharol and his family were travelling in the vehicle along with family friends Deepu Nair and Gopu Nair in Ibra when the accident occurred.
Sreeja and Adhu are battling for their lives in hospital.
Gopu had come from London to meet his brother Deepu, who lives in Oman.
The dead were identified as Veda (11) and Vaibhav (3) - the children of Tharol and Sreeja Tharol, both hailing from Kerala - and a son of Gopu Nair.
The wives of Tharol and Gopu - Sreeja and Adhu, respectively - are battling for their lives in hospital, the report said.