MANILA, Philippines — Less than 12 incumbent lawmakers have been tagged in alleged anomalies surrounding public works projects, an official of President Rodrigo Duterte's anti-corruption body said Wednesday.

Greco Belgica, commissioner of the Presidential Anti-Corruption Commission (PACC), said the lawmakers were mentioned in complaints about irregularities like ghost projects, kickbacks, repeat funding and substandard projects.

"Yung exact number is less than 12, ang alam ko, ang naisubmit sa pangulo na nakita namin after validation (I think the exact number submitted to the president after validation is less than 12)," Belgica told CNN Philippines.

"This has to be investigated formally. We need solid documents. We need probably a forensic of the projects...All of these should be substantiated so a case can be filed," he added.

In a separate interview with Teleradyo, Belgica said the allegedly anomalous projects that were tied to lawmakers are located in four regions. The possible involvement of regional public works directors in the supposed irregularities would also have to be probed, he added.

Asked whether the lawmakers are allies of Duterte, Belgica replied: "I'm not privy to their relationship with the president. It's immaterial to me."

Belgica said the kickbacks supposedly demanded by the lawmakers ranges from 5% to 15%. He said one witness is claiming that a lawmaker had sought a 10% commission from a P100-million project.

"I'm not saying this applies to all congressmen. All of these have to be substantiated and validated so the cases can stand in court," the PACC commissioner said.

Belgica, however, clarified that the PACC probe focuses on public works projects, noting that the body only has jurisdiction over presidential appointees.

"In the course of our investigation, there are witnesses who came forward with documents, some were complaining about congressmen asking for kickbacks... When we reach the point where there are reports that are beyond our jurisdiction, we submit the information to competent authorities because we don't have jurisdiction over elective officials," he said.

Last Monday, Duterte said he will not expose the lawmakers tagged in the alleged corruption in state projects, saying he has no jurisdiction over officials who are not part of the executive branch. The president said he has no authority to identify the lawmakers and that he would encroach upon the separation of powers if he probes members of the legislature. Duterte said the list of lawmakers tied to corruption should be submitted to the ombudsman because it is "the only investigating agency that has jurisdiction over congressmen."

Belgica said Duterte was right in saying that the corruption allegations against lawmakers should be investigated by the ombudsman.

"We submit our reports to the president to ask for direction. Correctly and rightly, the president said 'investigate, bring it to the ombudsman and the (mega anti-corruption) task force," the PACC official said.

"When you bring it to the ombudsman, bring it to the task force, that means technically, impliedly, we should investigate. which is the proper thing to do so it would be fair, professional and formal. Allegations have to be substantiated and the accused will be asked to answer the allegations," he added.