Kenyatta National Hospital (KNH) has confirmed that a hawker shot during Tuesday’s protests in Nairobi is still in critical condition after undergoing emergency surgery.

Dr. William Sigilai, the hospital’s CEO, told reporters on Wednesday that the man had surgery to remove a foreign object from the left side of his head—believed to be a bullet or rubber projectile. He’s now in the Intensive Care Unit.

“We can’t say for sure what type of bullet it was. All objects removed from the injured are being analyzed,” Dr. Sigilai said. “We suspect it might be rubber, but we are not ballistics experts.”

The hawker, identified by his father as 22-year-old Boniface Kariuki, was selling face masks in Nairobi’s CBD when he was shot. His father, speaking to the media, said Boniface is the firstborn in a family of four.

The hospital also confirmed receiving 15 other casualties linked to the protests, bringing the total number treated on Tuesday to 16.

“Injuries ranged from gunshot wounds to blunt force trauma,” Dr. Sigilai added. Seven patients were admitted, while nine were treated and sent home. By Wednesday, two had undergone surgery and four others were still awaiting operations.

One patient remains unidentified. He came in with serious skull fractures after being hit in the head.

Meanwhile, the two police officers believed to have been involved in the shooting were arrested shortly after the incident. They are expected to appear in court on Wednesday.