BP PLC (BP) managers may be subpoenaed in connection with a criminal probe of the company's catastrophic oil spill in the Gulf of Mexico, Bloomberg News reported Friday, citing a person familiar with the investigation. Justice Department lawyers reportedly urged that a grand jury be convened to compel testimony from the BP managers. Among those who would testify under oath include contractors who worked for BP and offshore drilling regulators involved in the approval of the Deepwater Horizon rig, the site of an April 20 explosion that killed 11 people and unleashed a massive oil spill. Though the Justice Department has said it is investigating the incident, no formal charges have been filed. (END) Dow Jones Newswires July 30, 2010 13:31 ET (17:31 GMT)