MANILA, May 13 (Reuters) - Shares in two Philippine firms owned by a tycoon and close associate of outgoing President Rodrigo Duterte tumbled in early trading on Friday, after Reuters reported a potential sale of the companies.

DITO CME, owner of the country's third-biggest telecoms operator, and Chelsea Logistics lost 7% and 3.8%, respectively, bucking a 0.3% gain in the broader stock index. (Reporting by Neil Jerome Morales Editing by Ed Davies)