A fire crew had to remove the window of a bus to recover the body of an overweight man who died suddenly.
The man's body was discovered last night on the No 66 bus as it approached Leixlip, Co Kildare, at about 7pm.
He is believed to have been in his 40s. The death is not believed to be suspicious.
A Dublin Bus spokesperson said: "There were around 15 passengers on the No 66 bus and a couple of passengers noticed that a man on the upper saloon looked particularly ill.
"They alerted the driver who immediately contacted the emergency services who went to the scene.
"I understand that at this stage the man had passed away, sadly. He was taken away by the emergency services."
A Dublin Fire Brigade spokesman said they were not involved in the action to recover the man's body, but understood a local brigade unit had been called to the scene.
A garda spokesman said the death was being investigated but it is believed the man died of natural causes.
The body was removed to Naas General Hospital where a post-mortem examination was due to be carried out today.
Meanwhile, a young mother and her two-year-old daughter were fighting for their lives after a head-on collision in a Co Clare village.
The 22-year-old woman and her daughter were said to be in a critical but stable condition.
The woman's other child, a five-year- old girl, suffered less serious injuries.
The accident happened in the village of Darragh at 2.45pm yesterday on the N68 road from Ennis to Kilrush.
The male driver of the other car involved is understood to have suffered minor injuries.
The man, in his early 40s, tragically lost his own son in a traffic accident in Co Kerry just over a fortnight ago.
Gardai are investigating the possibility that one of the drivers involved may have been temporarily blinded by the sun's glare.