Metro Manila (CNN Philippines) – The fight is not yet over for relatives of some of the 44 police commandos killed in Mamasapano, Maguindanao four years ago, as they sought to reopen the investigation on the botched operation.

Five complainants, with the help of advocacy group Volunteers Against Crime and Corruption, filed Friday a petition seeking to charge former President Benigno "Noynoy" Aquino III with "reckless imprudence resulting in multiple homicide" before the anti-graft court.

"Thus, in view of the foregoing, we are respectfully urging the Ombudsman to reopen the ... case against former President Benigno Simeon Aquino III for the deaths of the SAF 44," Erlinda Allaga, Julie Danao, Celestino Kiangan, Felicitas Nacino and Arsenio Evangelista said in their motion.

They also said in their appeal that even if Aquino is no longer a government official, the case could be re-investigated if another complaint against him is filed, quoting Ombudsman Samuel Martires.

They also submitted an affidavit of former PNP–Criminal Investigation and Detection Group head Benjamin Magalong as additional evidence. Magalong was the officer who affirmed Aquino's hand in the Mamasapano incident. Magalong is now Baguio City mayor.

In July 2017, then Ombudsman Conchita Carpio Morales junked the complaint of reckless imprudence resulting in multiple homicide against Aquino as well as former Philippine National Police chief Alan Purisima and former PNP-Special Action Forces Commander Getulio Napeñas Jr. for “lack of probable cause.”

But Carpio-Morales found probable cause to charge Aquino, Purisima and Napeñas for graft and usurpation of authority under the Revised Penal Code. She said there was an alleged conspiracy because Aquino allowed Purisima to have a role in the failed operations even if he was suspended at the time.

In January 2018, the Office of the Solicitor General asked the Supreme Court to charge Aquino with homicide instead of graft, but it was denied by the high court’s First Division on September 2019, clearing Aquino of all charges in relation to the SAF 44 killing.

Supreme Court Chief Justice Peralta, for his part, said he will leave it to the Ombudsman to decide on whether there is sufficient basis to re-investigate the homicide complaint against Aquino.

"Let the Ombudsman rule on that," he said as Peralta spoke with the members of the media as chief justice for the first time.

The magistrate added that the determination of probable cause is the role given to the lower court, and if the SC rules on that, it will "encroach" on their power.

READ: Ex-President Aquino faces criminal raps over Mamasapano encounter, cleared of homicide