THE camp of administration standard-bearer Manuel Roxas II blasted Thursday presidential aspirant Davao City Mayor Rodrigo Duterte over his alleged ties with some businessmen involved in the mining industry.

Caloocan City Representative Edgar Erice, Liberal Party (LP) vice chair for political affairs, said that Duterte should disclosed his supposed connection with businessmen Manuel Zamora and Dennis Uy who were reportedly financing his national campaign for the upcoming 2016 polls.

Both Zamora and Uy are involved in mining firms operating Mindanao.

"(Mayor) Duterte has been boasting that he will not receive financial contributions from big business in order to avoid being beholden to them if he wins the presidency, (pero ano itong mga nakapaligid sa kanya? Hindi ba mga malalaking minero din?)" said Erice.

Last month, Duterte launched an offensive against Roxas for allegedly accepting material and financial support from San Roque Metals Inc. owned by businessman Francis Eric Gutierrez and reportedly a business partner of Erice, who is engaged in nickel mining in of Mindanao.

The presidential frontrunner took a swipe at Roxas for using SRMI resources, including its helicopter, for his provincial sorties.

Erice said that Zamora, founder of the Mindanao-based mining firm Nickel Asia Corporation, has been helping Duterte with his media campaign.

Zamora, brother of San Juan City Representative and House Minority Floor Leader Ronaldo Zamora, has been engaged in mining in Mindanao since 1969.

He founded the Rio Tuba Nickel Mining Corporation and the Taganito Mining Corporation. He also serves as director of Hinatuan Mining Corporation and Cagdianao Mining Corporation.

Erice said that the mining magnate has tapped a public relations group through Senator Alan Peter Cayetano, Duterte's running mate, to take care of the Duterte's media campaign operations.

Duterte's spokesperson Peter Lavina earlier said that media and public relations operations are under the domain of Cayetano's group.

Erice said he also received reports that Uy is among Duterte's biggest financial backers.

Uy's is a member of the board of directors of mining firms Apex, Bulbscor and Blucor, all engaged in diamond and silver mining operations in various parts of Mindanao. (Sunnex)