San Francisco has launched a multilingual hotline to prevent election fraud.

The hotline is available in English, Spanish, Cantonese and Mandarin.

District Attorney George Gascon said citizens can call the hotline if they witness anything that raises concerns about improper voting.

"We want to make sure that if there's some allegations about behavior, that we can get to it very early on in order to be able to protect any evidence," Gascon said, "to ensure that if there is a prosecutable case, we can do so."

Investigators will be responding to hotline calls up to Election Day. The phone number is (415) 551-9548.