Police responded at 2:52 a.m. to a report that a car crashed into a structure in the 1200 block of South Second Street.
Officers arrived to find a tan 1997 Ford four-door sedan but its driver had fled on foot, police Officer Jose Garcia said.
The crash ruptured a natural gas main, causing a leak that prompted the evacuation of several nearby homes. At least 20 people were evacuated from the area, Garcia said.
PG&E crews responded to shut off the gas, and authorities closed surrounding roads.
The area was deemed safe and residents were allowed to return to their homes shortly after 5:30 a.m., a fire dispatcher said. No injuries were reported due to the leak, the dispatcher said.
Roads in the area remained closed to traffic this morning while PG&E crews dig to repair the broken gas main.
PG&E spokeswoman Jana Morris said 10 customers were without service this morning due to the incident, and she did not know when their service would be restored.
The driver of the Ford had not been found as of 8:45 a.m. this morning, and the car has been impounded, police said.