Thirty-eight people were killed and 19 were injured when a bus plunged off a viaduct in the southern Italian province of Avellino.

Media outlets said that this was one of the worst traffic accidents ever in Italy and noted that it occurred on a stretch of highway where in recent years there have been nearly a score of deadly crashes.

All but 10 of the 48 people aboard the bus lost their lives, including the driver.

Nine of the injured were people traveling in other vehicles that the bus struck before running off the road.

An investigation has been launched to determine why the bus first hit the vehicles in front of it and then crashed through the guardrail and fell some 30 meters (98 feet) to the ground below.

Rescue teams and several witnesses who were at the scene shortly after 9 p.m. Sunday said that the portion of the highway between Bari and Naples was "hell."

The viaduct's guardrail was completely torn off and rescue teams were working below in the metal tangle of wreckage that had been the bus.

The emergency crews deployed to the scene had great difficulty accessing the spot where the bus had come to rest and said they could hear the cries and weeping of the survivors, among whom were several children.

The victims were all friends and acquaintances living in three towns in southern Italy who often organized excursions together.

On Sunday, they had been returning from a weekend at the Telese Terme resort and a visit in Pietrelcina, the birthplace Padre Pio, one of the most venerated saints in Italy. EFE