Police are now hunting for the gunman who opened fire near a hospital in the wealthy 16th district of the French capital, killing one person and injuring another.
Witnesses at the scene suggested it could be a case of tragic score-settling, while authorities have not made any links with terrorism.
Paris police said the gunman fired several shots before fleeing on a two-wheeled vehicle.
Noura Berrahmouni, of the DSPAP Alliance, said the injured person, a woman, was a security agent for the hospital.
"It was so fast we suppose it was a score-settling ... If not, we think there would be more victims," she said.
The gunman wore a hood and fired several times, according to witnesses on BFM-TV.