FERGUSON, Mo. -- Two police officers were shot early Thursday outside the Ferguson police station, the St. Louis County police said.
One officer, from the county police department, was shot in the shoulder, and the other, from the St. Louis suburb of Webster Groves, was shot in the face, the county police said. They were being treated at a St. Louis hospital. The county police chief, Jon Belmar, said their injuries were "serious."
"I don't know who did the shooting, to be honest with you," Belmar said at a news conference. He said that based on the bullets' trajectory and where the officers had been standing, he assumed that "these shots were directed exactly at my police officers."
He said he did not know what kind of gun had been used.
The shootings occurred after a crowd gathered outside Ferguson police headquarters as news spread that the city's police chief, Thomas Jackson, had agreed to resign as part of a shake-up of the city's administration in the wake of the shooting death of a black teenager, Michael Brown, by a white police officer in August.
The resignations of both Jackson and Ferguson's city manager, John Shaw, who stepped down Tuesday, followed a scathing Justice Department report on constitutional abuses in the local law enforcement system.
The protests late Wednesday and early Thursday included occasional clashes with the police and a few arrests. But the situation had been relatively calm until shots were heard shortly after midnight.
Protesters and police officers immediately hit the ground. After the gunfire stopped, several officers appeared to be dragging a colleague back toward the police station.
"I heard the bullets go past my head," said Bradley J. Rayford, a freelance photographer, who said he was standing near police officers when the shots were fired.
After the first shot, Rayford said, he looked up at a hill across from the police station and saw muzzle fire from that direction. He said he heard about four shots, after which he went to the ground.
When the shots were fired, the officers were lined up in front of the station in riot gear, in a scene that was reminiscent of the sometimes unruly demonstrations after Brown was shot.
Earlier in the evening, several dozen protesters had blocked the street and chanted in front of the police department. There were tense moments when protesters surrounded cars that tried to get through. At times, police wearing helmets and holding shields and batons rushed into the street to push demonstrators out before retreating.
It was the busiest night of protest here since a grand jury declined to indict Officer Darren Wilson in Brown's death.
After the shots were fired, the remaining protesters scattered, and the St. Louis County Police Department's homicide unit was sent to investigate.
Dozens of officers from around the region also arrived. Several held rifles and crouched behind cars, walls and gates. A group of officers in tactical gear carefully walked up the hill across from the police station where Rayford and other witnesses said the shots had come from.
By 2 a.m., a handful of people remained in the lot across from the department, which was encircled in yellow police tape. Investigators attempted to interview people in the group, but many were reluctant to talk.