Rome, October 19 - A manager for the Parma-based construction company Bonatti is under investigation in relation to the killing this year of two Italians taken hostage in Libya - Salvatore Failla and Fausto Piano, sources said on Wednesday. Dennis Morson, Bonatti's logistics chief for Libya, is probed for suspected culpable homicide and breaching regulations on safe working conditions, the sources said. Carabinieri police on Wednesday searched the offices of Bonatti to gather evidence for the probe, sources said. Failla and Piano were killed on March 2, apparently in a firefight between the kidnappers and militia loyal to the Tripoli national unity government, although the circumstances are still not entirely clear. They were taken captive along with two other Italian hostages, Filippo Calcagno and Gino Pollicardo. Calcagno and Pollicardo broke out of the house they were being held in in the city of Sabratha a day after Failla and Piano were killed.