Last month, a domestic abuse victim successfully signaled for help at a convenience store in California without alerting her alleged abuser, who was with her at the time.

She was able to do this through the use of a hand signal, according to police.

According to the Alhambra Police Department, during the August 19 incident, the victim discreetly asked for help using hand signals behind her back. This led to the determination that a domestic violence situation had occurred.

Authorities did not specify which gestures were used by the woman. However, organizations that support women and domestic violence victims advocate for the “Signal for Help,” a gesture developed by the Canadian Women’s Foundation for situations where victims are being monitored and cannot speak openly.

The foundation created this gesture early in the pandemic due to an increased risk of gender-based violence among quarantined household members, a representative informed Nexstar. United Nations agency data reviewed at the time showed intensified violence, exacerbated by factors like lack of support, financial troubles, and alcohol abuse.

The signal, as it was designed, could be performed in silence from a distance, over video chat, or even through a window.

The Canadian Women’s Foundation describes the gesture as a simple, one-handed sign that leaves no digital trace, designed to prompt safe check-ins and support for those in need.

The signal is meant to be easy yet distinct: it involves showing an open palm, tucking the thumb inward, and closing the fingers over the thumb, symbolically “trapping” it.

But knowing how to perform the signal doesn’t mean onlookers know what to do once they see it. That’s why the Canadian Women’s Foundation urges supporters to become “responders” by taking action and reaching out safely, which can mean contacting them at a private phone number or email address. The foundation offers a guide and a mini-course with more information.

Organizations including the Canadian Women’s Foundation, the Women’s Funding Network and the U.S. Department of Veterans Affairs have promoted the use of the Signal for Help, adding that onlookers should call the authorities if they believe a victim to be in immediate danger.

Arguably, however, the gesture has reached a much wider audience on TikTok, where tutorials explaining the significance and uses for the signal have been viewed millions of times. And those viewers are indeed putting that knowledge to use, helping to rescue victims.

In one such case from 2021, an abducted teen who learned about the Signal for Help on TikTok was able to alert a motorist to her predicament from the window of her abductor’s moving car. Speaking about the incident with The New York Times, Officer Gilbert Acciardo of the Laurel County Sheriff’s Office in Kentucky later said he wasn’t initially aware of the gesture, but quickly familiarized himself.

“This is probably the best thing I’ve seen come along in the 48 years I’ve been a patrol officer,” Officer Acciardo said.

Victims of domestic violence can contact the National Domestic Violence Hotline for additional support or resources by calling 1-800-799-SAFE or texting “START” to 88788. Online chat services are also available.