The Criminal Investigation and Detection Group (CIDG) has issued subpoenas to four alleged leaders of groups linked to the violent clashes that erupted during an anti-corruption protest in Manila on 21 September.

On Monday, CIDG spokesperson Police Maj. Helen dela Cruz disclosed that the four individuals were summoned to appear before investigators earlier in the day, but only one complied.

“The CIDG has issued subpoenas to four individuals, alleged leaders of four groups allegedly involved in the violent incident,” Dela Cruz told reporters. “Of the four, only one came.”

However, Dela Cruz declined to name the individuals or the groups involved, citing the ongoing investigation.

The four were reportedly identified based on statements from arrested protesters and on social media posts and video footage gathered by authorities.

She also stressed that under Republic Act 10973, the agency is empowered to issue such subpoenas in connection with its investigations.

Dela Cruz added that the agency will file a petition for indirect contempt of court against those who failed to comply.

Philippine National Police (PNP) spokesperson Police Brig. Gen. Randulf Tuaño cited that failure to comply with a CIDG subpoena could result in penalties of up to P30,000 in fines and six months of imprisonment.

To recall, the 21 September protest — held to denounce alleged corruption in government flood control projects — turned violent when unidentified men set tires on fire in front of a shipping container used as a police barricade.

Police reported that bottles, paint and rocks were thrown at officers. More than 200 individuals, including over 80 minors, were arrested during the chaos. The Department of Health later confirmed that one man died from a stabbing incident that occurred after the rally.

The CIDG is working to determine the extent of the groups’ involvement in the violence and whether there was any coordination or deliberate intent to incite disorder during the planned peaceful protest.

In other developments, The National Police Commission (Napolcom) on Monday commended several PNP units and personnel for their professionalism and restraint during the 21 September rallies held across the country.

The awards ceremony, held after the flag-raising ceremony at the Napolcom Central Office, recognized police units for ensuring the peaceful and orderly conduct of the nationwide demonstrations. Napolcom praised the police for their “adherence to the rule of law” and for strengthening public trust.