Metro Manila (CNN Philippines) — Philippine National Police (PNP) Chief Ronald 'Bato' Dela Rosa confirms police liability for the violent dispersal of a rally outside the U.S. Embassy last month.

Read: Dozens of militants, policemen hurt in clash outside U.S. Embassy

Dela Rosa said on Monday the PNP was done with the investigation of the incident and based on the their report, the driver of the police mobile — PO3 Franklin Kho — recklessly stepped on the gas to ram the vehicle into the crowd, injuring several protesters last October 19.

"His assertion that his acts were caused by his personal impulse to overcome imminent threat to life, in revving up the engine and recklessly accelerating and ramming the vehicle into the crowd of protesters which resulted to the injury of some persons, is not a valid excuse," the report said.

The investigators have also seen violations over the restraint and arrest of fleeing protesters on board jeepneys.

The report said, "(It is a) clear violation of the Police Operational Procedure and also contrary to the law."

The report added ground commanders Sr. Supt. Marcelo Pedroso and Supt. Albert Barot might be held liable for violations of operational procedures.

Meanwhile, PO1 Fernando Budong, will also be charged for carrying a gun-replica cigarette lighter and showing it to protesters during the dispersal.

The investigators recommend filing of two counts of grave misconduct cases against Kho, simple misconduct for Budong, and neglect of duty for Pedroso and Barot.

"The administrative portion it will be the IAS (Internal Affairs Service) who will do the administrative portion of that offense but for the criminal aspect yung complainant na nagsampa [filed by complainants]," Dela Rosa said. "But just the same, open ang PNP for filing (criminal) cases against them."

Read: Van driver, 39 other police officials relieved over violent U.S. Embassy dispersal

Meanwhile, the PNP also recommends filing of charges against some leaders of the protesters like Renato Reyes and Nathaniel Santiago of Bagong Alyansang Makabayan (BAYAN), Roberto De Castro of Kilusang Mayo Uno, Piya Macliing Malayao of Sandugo, and Jerome of Suara Bangsamoro for illegal assembly, direct assault, physical injuries and malicious mischief.

Malayao was among those injured in the incident.

"The leaders of the protest groups failed to police their unruly and violent members, which triggered the clash between the protesters and CDM (Civil Disturbance Management) personnel. The protesters' act of vandalism, aggressiveness, and assault on the policemen prompted the CDM contingent to disperse them," the report said.