The Mexican government says it foiled an international plot to smuggle one of Colonel Muammar Gaddafi's sons into Mexico, at the height of the Libyan uprising two months ago.
Saadi Gaddafi has been under house arrest in Niger, West Africa, since he fled Libya in September.
Lawyer Nick Kaufman denied he had ever tried to flout a UN travel ban and escape.
Mexican officials say the plot came to light through intelligence reports.
The BBC reports it involved buying a number of properties in Mexico, including one near the resort of Puerto Vallarta, using false names and documents, they said.
Several people were arrested on 10 and 11 November.
Mr Gaddafi is wanted by Interpol. The United Nations has frozen his assets.