LAS VEGAS (AP) - Firefighters have evacuated residents from four southwest Las Vegas apartment buildings where Southwest Gas crews are trying to trace the smell of natural gas and fix a leak if they find it.

Clark County spokesman Dan Kulin says at least 30 people were asked to leave after the odor was noticed about 1:30 p.m. Monday near Flamingo Road and Decatur Boulevard.

The American Red Cross of Southern Nevada says as many as 100 people are being evacuated.

No injuries are reported.

Officials planned to bring buses to the scene to provide people with an air-conditioned place to wait.

Southwest Gas spokeswoman Cynthia Messina says company workers at the scene didn't immediately find a leak or pinpoint where the smell originated.

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