The San Francisco Police Department wants to emphasize to the public that its text-message reporting program should not be used for emergency situations.
In emergencies, residents should call 911, police said.
For non-emergency reports, the department runs a Text-a-Tip program, which it launched last August.
Witnesses and other reporting parties can report criminal activity or supply crime-related information to police by texting TIP411, or 847411, with the keyword "SFPD" followed by the message.
Operations personnel review the tips around the clock, and forward tips for assignment to the appropriate investigative bureau or district station, according to police.
Investigators can text back and forth with the tipsters, who remain anonymous using a randomly assigned, confidential identification number unless the tipster provides personal information.
Alternatively, those with information they want to share can contact police using the department's confidential tip line at (415) 575-4444.