CAIRO (AP) — Egypt's highest appeals court on Sunday overturned the conviction of a police officer sentenced to 15 years in prison for the killing of a female protester in a January 2015 shooting captured on video and photos.

Cassation Court Judge Taha Qassim also ruled that a new trial be held for the officer, Yassin Hatem Salah Eddin, who was convicted and sentenced in June last year for premeditated manslaughter. Salah Eddin was 25 at the time of the killing.

The ruling, reported by Egypt's official MENA news agency, appeared to be in line with the acquittals or suspended sentences received by dozens of police officers who stood trial for the killing of nearly 900 protesters during the 18-day uprising that toppled autocrat Hosni Mubarak in 2011.

The Jan. 24, 2015 killing of Shaimaa el-Sabbagh, a 32-year-old activist and mother of a small boy, touched many Egyptians after images circulated of her with blood running down her face while leaning on another protester.

She and some 40 fellow members of a leftist party had gathered in downtown Cairo that day with the intention of laying wreaths at nearby Tahrir Square, birthplace of the 2011 uprising, in remembrance of protesters killed during the popular revolt.

Witnesses and members of her party later said that police ignored pleas to allow an ambulance through their lines to take el-Sabbagh away after she was shot with birdshot. They also prevented anyone from helping her, they said.

Authorities had initially denied that police had anything to do with the killing, and a senior police officer said at the time that forensic experts had determined the highly militarized force did not use the type of ammunition that caused her death, suggesting that an unknown party was behind the killing.

El-Sabbagh's death came amid widespread allegations of police brutality by local and international rights groups, which say the force has revived Mubarak-era practices like arbitrary arrests, torture and disappearances.

The policeman's defense lawyer, Farid El-Deeb, argued that the protest was held in violation of a 2013 law that effectively bans street demonstrations and that the circumstances surrounding it led to confusion among police officers assigned to enforce the law, according to the official MENA news agency.

The day after the shooting, another 23 people were killed, including three police officers, in violent protests as Egyptians marked the fourth anniversary of the start of the anti-Mubarak uprising.