The Jerusalem municipality said this week that the bulldozer operator who killed three people in central Jerusalem last week and wounded dozens of others was not employed by the city but worked for a private construction firm and so did not undergo the police screening required for city employees. The assailant, Hussam Dwayat, 30, who worked as a tractor operator for Achim Bardarian, an east Jerusalem based construction company - despite his past criminal record - was working on a private building project near the site of Wednesday's attack, and was not carrying out infrastructure work for the city's light rail system as was initially assumed by police. Shmuel Elgrably, a spokesman for the light rail project, said that Dwayat's employers had been working on a private housing complex nearby. The company refused comment on the issue Tuesday, and hung up the phone. Separately, Jerusalem police said that employers did not have the right to ask their employees for a police listing of their criminal records, and that by law only certain organizations - such as the security services but also the Jerusalem municipality - can ask employees for a certificate of honesty informing employers if they have a criminal background.