NEW YORK — Authorities searched Sunday for a man who shot a police officer in the arm in Ferguson, Mo., on Saturday night, in an episode that they said was unrelated to continuing protests over the death of a black teenager shot by a white officer there last month.
The officer was shot around 9:10 p.m. while checking on a community center, Ferguson Police Chief Thomas Jackson said in a news conference. The center is not near where the protesters had gathered.
The officer spotted two men, who began running when he approached them, Jackson said. The officer chased them, and as he closed in on one of the men, the chief said, the second pulled out a gun and fired at the officer.
The officer said he fired several shots in return, but there was no indication that he had hit either man, Jackson said.
The man who shot the officer fled into woods, the St. Louis County Police Department said Sunday morning. Ferguson police officers and officers from other departments searched the area for an hour and a half but did not find him.
Officials did not release the officer’s name or say how long he had been on the police force. Initial reports that the injured officer was a woman were incorrect. The officer, who was shot once in his left arm, was treated at a hospital.
The shooting occurred in a neighborhood off West Florissant Avenue, a major artery in the area, about 2 miles from where the teenager, Michael Brown, was shot and killed by Officer Darren Wilson on Aug. 9. Jackson said he did not think the shooting was related to protests over Brown’s death.
“It didn’t happen within the proximity of the protest area,” he said. ‘‘This is a fairly secluded area. I wouldn’t have any reason to think that it was linked in any way, shape, or form.”
The St. Louis County Police Department is conducting the investigation into the shooting.
Less than an hour after Jackson spoke, an off-duty St. Louis city police officer was shot at while driving his personal vehicle on a highway near Ferguson, the County Police Department said. The officer suffered minor injuries from breaking glass when his vehicle was struck several times by the gunfire.
A car pulled up next to the officer’s vehicle on Interstate 70 near the St. Louis International Airport around 12:10 a.m. Sunday, officials said. People inside the car fired several shots at the officer’s vehicle.
“It is unclear at this time if the officer was targeted or if this was a random act of violence,” the County Police Department said in a statement Sunday morning.
Schron Jackson, a spokeswoman for the St. Louis Municipal Police Department, said the suspects, described as three males, fled in a black sedan. The officer, who was wearing his uniform pants but not his uniform shirt, did not return fire, officials said.
Governor Jay Nixon of Missouri expressed sympathy for the two injured officers in a conference call Sunday from Afghanistan with reporters from Missouri. He described the violence as ‘‘a challenge for everyone.’’
Demonstrators have been protesting in Ferguson since Brown’s death, in a case that has heightened long-simmering racial tensions in Ferguson, a suburb north of St. Louis.
At around midnight Saturday, about two dozen officers stood near a group of about 100 protesters who mingled on a street corner, occasionally shouting, ‘‘No justice, no peace.’’ By Sunday afternoon, the streets of Ferguson were quiet, with no visible signs of police or protesters.
On Thursday, Chief Thomas Jackson of the Ferguson Police Department issued a stark apology to the relatives of Brown, saying in a videotaped statement that he was sorry for the death of their son and for the four hours that the body of the unarmed 18-year-old lay in the street.
“I want to say this to the Brown family: No one who has not experienced the loss of a child can understand what you’re feeling,” he said. “I am truly sorry for the loss of your son. I’m also sorry that it took so long to remove Michael from the street.”
But in an interview with the Associated Press on Saturday, Brown’s parents were unmoved.
Brown’s mother, Lesley McSpadden, said, “Yes,” when asked if Jackson should be fired. And his father, Michael Brown Sr., said that rather than an apology, they would prefer to see the officer who had shot their son be arrested.
“An apology would be when Darren Wilson has handcuffs, processed and charged with murder,” Brown said.
McSpadden and Brown attended President Obama’s speech at the Congressional Black Caucus Foundation awards dinner on Saturday. He acknowledged their presence in the audience during his remarks, in which he also said more progress is needed in curbing racial discrimination.