Two people were killed and seven injured when they were struck by a vehicle on a busy street in New Orleans on Saturday night.
A police spokesman said on Sunday the man arrested was believed to have been impaired at the time.
In a news release, Andy Cunningham identified the suspect as 32-year-old Tashonty Toney and said he was the son of a New Orleans police officer. Cunningham said the discovery will not change the department’s investigation, which he said will be “open and transparent”.
According to the news release, Saturday was Toney’s birthday. Police were awaiting the results of a blood alcohol test.
Police initially said six people were also injured in the crash. But Cunningham said another victim who did not seek assistance at the scene was later taken to the hospital in a private vehicle.
Toney faces two counts of vehicular homicide, seven counts of vehicular negligent injury, hit and run and reckless operation.
The incident happened at around 8pm on Saturday, along a multiple-block stretch of Esplanade Avenue.
“We were able to apprehend the subject quickly because citizens stopped this individual, because they thought they were helping someone who had just been involved in a one-car accident,” Supt Shaun Ferguson said.
One witness, Frank Rourk, told the New Orleans Advocate he saw a driver of a dark sports car spin out on the median. The driver ran off but then laid down on the sidewalk, where he lost consciousness.
Rourk and two other people were able to wake the driver, and Rourk, who initially did not realize anyone was hit, told the driver: “I’m pretty sure you’re the guy who wrecked the car. You better go back there.” The driver then asked if he had killed anyone.
The people killed were a man and a woman both aged about 30, New Orleans emergency medical services said. The injured ranged in ages from 28 to 65. Three were in critical condition.
Photographs of the scene showed mangled bicycles along the side of the street.
One onlooker, Dane Barrymore, told the Advocate he saw a dark sports car speeding down the street. The driver swerved into the bike lane to try to go around a vehicle.
“It just happened there were people there – bicyclists,” Barrymore said.
The incident happened not far from the Endymion parade, where one of the city’s biggest Mardi Gras parades takes place.