MEXICO CITY, March 23 (Reuters) - The chief executive of a major Mexican oilfield services company was held for questioning on Saturday in connection with a fraud investigation that forced Citigroup to cut its 2013 profit, the federal attorney general's office said on Sunday.
Amado Yanez, CEO and majority owner of Oceanografia, presented himself voluntarily for questioning, the attorney general's office said in a statement. The attorney general had also requested a temporary detention order that would forbid Yanez from travelling.
Local media reported that the questioning continued through Sunday.
Oceanografia was a top service provider to state-run oil giant Pemex over the past decade, winning billions of dollars in contracts as a supplier of engineering and maintenance services on offshore oil platforms and pipelines.
Citigroup Inc said last month it uncovered at least $400 million in bogus loans to Oceanografia at its Mexican subsidiary, Banamex.
The bank said it discovered the fraud after reviewing invoices Oceanografia said it was owed by Pemex, but Citigroup found that the invoices were not valid.
Mexico's government has taken control of Oceanografia and begun a criminal investigation. The U.S. Federal Bureau of Investigation and Securities and Exchange Commission are also investigating the transactions, people familiar with the probes have said. (Reporting by David Alire Garcia; Editing by Miral Fahmy)