(ANSA) - Palermo, August 10 - Two boys aged 13 and 14 drowned off Ustica Thursday evening after the car they were travelling on plunged into the sea. One of the boy lost control after taking the wheel of the vehicle - a Fiat Panda reportedly belonging to a pensioner that had been left unlocked with the keys in the ignition - in the island's port around 10 pm local time. Local scuba divers intervened immediately to rescue the boys but they had already drowned. One of the boys was the son of a Tunisian artisan who has lived and worked on the Sicilian island for many years and the other was the son of the local ambulance driver. Prosecutors in Palermo have opened an investigation into the incident.