Three police officers were killed in Puerto Rico on Monday when a carjacker opened fire at them and ran over one of the officers in the middle of a busy expressway, the authorities said.
The carjacker remained at large on Monday night after leading the police on a chase outside San Juan that left a fourth officer hospitalized in stable condition with unspecified injuries, officials said.
The episode happened around midafternoon on Expreso Román Baldorioty de Castro, a major highway that connects San Juan with the city’s main airport and cuts through a popular beach resort area.
The sounds of a hail of gunfire and screeching tires were captured on video by motorists on the congested expressway.
Details of the encounter were not immediately available, though a police official told The Associated Press that two of the officers had been shot and that the third had been run over. That official later referred questions on the matter to a spokeswoman, who did not immediately respond to a request for comment on Monday night.
Gov. Pedro R. Pierluisi of Puerto Rico said in a Facebook post that investigators would work tirelessly to bring the killer to justice.
“This loss of life needs to end now,” Mr. Pierluisi said. “Our people and these families deserve more.”
Mr. Pierluisi said he had spoken to the injured officer and wished him well in his recovery.
The names of the officers who were killed were not released by the authorities, who said two of them were municipal police officers and one was a state police officer.
The mayor of San Juan, Miguel Romero Lugo, ordered the flags at city buildings to be flown at half-staff for three days.
“They risk their lives daily to become the anonymous heroes of Puerto Rico,” Mr. Lugo said in a statement.
Alexis Torres, the secretary of the Department of Public Safety in Puerto Rico, said on Twitter that the law enforcement community was heartbroken by the deaths of the officers.
“To the relatives of the deceased colleagues, my solidarity, support and prayers in this moment of deep pain,” Mr. Torres said. “I pray to God for the rest of their souls and for strength so that their families can face this difficult situation.”
It was not the first time in Puerto Rico’s recent history that three police officers were killed in one episode. In 2015, a police officer who once had his department-issued firearm taken away while he underwent psychological treatment gunned down two superiors and a third colleague.
Puerto Rico, reeling in the wake of bankruptcy and the devastation of Hurricane Maria, is enduring a sinking economy and a mass exodus. The island has long had one of the highest murder rates in the United States, almost all of it attributable to gang violence.
More recently, a spree of brazen daylight killings, some of which were captured on video and widely shared on social media, rattled residents and worried local and federal law enforcement officials who thought they had seen everything in the roiling, populous capital city.
Sheelagh McNeill contributed research.