The National Bureau of Investigation (NBI) on Friday warned that those behind an alleged smear campaign and other illegal activities would face criminal charges as investigators expanded their probe into an alleged plot to frame Executive Secretary Ralph Recto.

NBI Director Melvin Matibag said investigators have identified several personalities believed to be involved and will summon them for questioning as the bureau determines their individual liabilities.

"We will always be guided by law, evidence and procedure," Matibag told reporters.

"I'm warning all those who are planning to engage in character assassination or commit illegal acts against anyone, not only those in the administration. Whoever they are, we will investigate them. No one is exempt."

Matibag said investigators already have leads on those allegedly behind the operation, which he described as well-funded.

"We already have an idea who the players are," he said, adding that investigators are still gathering evidence before filing possible charges.

The NBI chief said authorities are also looking into whether the alleged operation was part of a broader effort targeting other public officials.

"If this operation had succeeded, others could have been next, possibly even senators," Matibag said. "We are looking at the direction of the investigation."

Matibag said former Negros Oriental Rep. Jacinto "Jing" Paras would be summoned once investigators complete the necessary procedures.

He also said the bureau would subpoena Batangas 1st District Rep. Leandro Leviste over allegations contained in the affidavit of an arrested talent manager, who claimed there was a plan to frame Recto through a purported "bug" or human trafficking scheme.

The subpoenas are expected to be issued Friday, requiring the two to appear before the NBI on Wednesday or Thursday next week.

"Magbigay-linaw sila dito kasi mahirap namang sa social media mo lang itatanggi," Matibag said.

The NBI-NCR conducted an entrapment operation at a five-star hotel in Manila on Tuesday, leading to the arrest of the talent manager and the rescue of several women.

Matibag also disclosed that investigators recovered screenshots of alleged online conversations involving Paras, adding that some of the messages had later been deleted.

He said Paras voluntarily surrendered his mobile phone to the bureau. Electronic devices allegedly used in the commission of a crime may be examined as evidence, he said, while cyber warrants provide an additional legal basis for accessing digital data.

The NBI chief added that investigators received information indicating some of the personalities involved had discussed holding a press conference.

On Thursday, the bureau disclosed that an anti-human trafficking operation in Manila uncovered an alleged plot to frame Recto.

According to the NBI, the arrested talent manager claimed he had been approached to make it appear that Recto was one of his clients. The suspect alleged that Paras contacted him regarding the plan and that Leviste financed the supposed operation.

The suspect further claimed that he and four women were each promised P1 million to falsely accuse Recto of forcing them to use illegal drugs and engage in sexual acts.

The NBI stressed that these allegations came solely from the arrested suspect and have not been independently verified. The investigation remains ongoing.

Matibag said the bureau would pursue anyone found to have violated the law, regardless of political affiliation.

"Do not think of doing something illegal because the NBI is proactive," he said. "We will always enforce the law."