Guzman, who has escaped prison twice, himself said he didn't believe his business had been impacted by his last spell in prison.

Penn said Guzman sent engineers to Germany for three months of training on how to avoid problems when excavating near a low-lying water table beneath the prison where he was being held in order to perfect the audacious escape plan.

Guzman also revealed to Penn that he had once met Colombian Pablo Escobar, perhaps the world's most notorious cocaine trafficker "at his house. Big house."

One Mexican government source said authorities were considering whether to investigate Penn and Del Castillo, possibly for money laundering. The source did not explain further.