(UPDATE) Lawyer Manases Carpio on Tuesday explained why he was seen visiting the Bureau of Customs amid allegations that a so-called Davao Group is behind corrupt activities in the bureau.

"I represent many clients who have transactions with the Bureau of Customs. It is my job as a lawyer to appear before government agencies for and on behalf of my principals," Carpio said in a statement.

The lawyer also twitted Sen. Antonio Trillanes for asking about his appearance at the bureau.

"Senator Trillanes is imputing malice in saying that my appearance before the BOC is because of smuggling. He is just a desperate rumor monger who happens to be a senator," Carpio added.

The senator earlier said he wants the Senate Blue Ribbon Committee to verify the existence of the so-called "Davao Group," which is being linked to corruption in the Bureau of Customs.

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During a Senate Blue Ribbon Committee hearing, Trillanes asked several Customs officials if they saw Carpio, husband of Davao Mayor Sara Duterte, lingering in the BOC's premises.

"Si Atty. Mans, nakita kong pumasyal sa BOC, your honor, but not Paolo Duterte... I am not privy to the situation. I just came down from my office and I chanced upon him (Carpio) going out," resigned Customs Intelligence chief Neil Estrella told lawmakers.

• Duterte son in-law visited Customs, says ex-BOC intel chief

Estrella also said he has no information that Davao City vice mayor Paolo Duterte, son of President Duterte, had ever visited Customs.

OMBUDSMAN REACTS

Meanwhile, Ombudsman Conchita Carpio Morales said she is unaware of the activities of her relatives in Davao City including that of her nephew, Manases.

"I am neither privy nor updated on the activities of my relatives in Davao," she said.

"I inhibit from issues that may lead to cases vs Duterte but certainly a complaint filed vs any of my own relatives holding public office will be dealt with as with other similar cases...according to the applicable law and the evidence," she added.