Around 9,000 police officers signed a petition pleading for mercy for two colleagues charged with negligent homicide in the death of a protester by a blast from a police water cannon during a street rally.

The two, identified by their surname Han and Choi, were indicted by the Seoul Central District Prosecutors’ Office last month for violating safety guidelines when they tried to contain an anti-government rally in central Seoul in November 2015 with a water cannon.

Baek Nam-gi, a 65-year-old activist farmer at the protest, was knocked down by a water jet. He died in September last year after 10 months in a coma.

“They have been loyal and dedicated police officers. The two and their families did and will continue to suffer from the consequences (of their actions). I sincerely hope (the court) shows mercy within the boundary of the law to the officers and their heartbroken families,” the petition reads.

Initiated by the charged officers’ colleagues at Chungnam Provincial Police Agency, the petition had gathered 8,850 signatures as of Monday.

The case has been highly controversial, with the previous administration seen as refusing to take responsibility. Even his cause of death was altered from illness to external causes nine months after the autopsy, or three months after the removal from office of former President Park Geun-hye.

The prosecution, following the Seoul National University Hospital’s rare correction of the death certificate, resume the stalled probe into his death.

Earlier this month, prosecutors concluded that police were responsible for directing the water cannon operation, indicting then-commissioner of the Seoul Metropolitan Police Agency Goo Eun-soo and then-chief of the riot squad Shin Yun-kyun on charges of negligent homicide.

Along with the former police leadership, low-level officers Han and Choi, who handled the water cannon at the scene, were indicted for failing to follow a regulation that bans firing water cannons directly at a person above the chest.

Han and Choi had submitted a document to the court last month saying they would bear all the responsibility over the death of the activist in a separate civil suit filed by Baek’s family.

Police in May announced a set of reform measures that includes a ban on the use of water cannons and bus barricades at street rallies.

By Bak Se-hwan (sh@heraldcorp.com)