MANILA - Former Senator Ferdinand "Bongbong" Marcos Jr. on Monday sought an investigation into the alleged outing last month attended by an employee of Vice President Leni Robredo and some personnel of the Presidential Electoral Tribunal.

Marcos, who lost to Robredo by 263,473 votes in the 2016 elections, filed a "manifestation of grave concern" to ask the Supreme Court, which sits as the PET, to look into the supposed outing in Calamba, Laguna.

It was allegedly attended by poll recount revisor Osmundo Abuyuan, who is tasked to claim or object to ballots for Robredo, and PET-hired head revisors, alternate head revisor, ballot custodians/handlers, appraiser, chief tabulator.

Marcos said he was dismayed with the outing and it was plausible that Robredo camp has “infiltrated” PET personnel so as to “manipulate, influence, and/or control” the ongoing poll recount.

The former senator's camp attached photos posted on social media to its formal manifestation.

Marcos had claimed "massive cheating" behind his loss to Robredo in the vice-presidential race, which was the closest in recent memory.

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