Naples, July 29 - Police said on Monday that they are investigating the braking system and tires of a bus that fell some 30 meters from a bridge overnight Sunday in southern Italy, killing 38 and injuring another 10. The group of friends was returning from a weekend excursion to the local Telese thermal baths and the popular pilgrimage destination of Pietralcina, home town of the Italian saint Padre Pio. Rescue crews worked overnight to extract survivors and victims from the wreckage, and a local school was converted temporarily into a morgue while the bodies are being identified. Police investigating said that there were no skid marks indicating that the driver had braked. The driver bumped into six cars before the bus slammed into the guardrail and flew from the high viaduct, police said. All of the passengers were long-time friends who frequently took trips together organized by a delicatessen owner from Pozzuoli, Luciano Caiazzo. At least five children were on the bus, all of whom survived. Italian Premier Enrico Letta cancelled a planned visit to the Acropolis in Athens on Monday, but will continue with the rest of his itinerary in Greece as planned.