Fewer domestic violence calls during COVID-19 outbreak has California officials concerned Authorities are worried victims are unable to get help while quarantined.

Since the beginning of COVID-19-related stay-at-home orders, police and advocacy groups across the country have warned that domestic violence calls could increase with people being cooped up at home, tempers more likely to flare, abusers more likely to lash out.

And although data in a few of America's largest cities initially suggests otherwise, multiple agencies told ABC News that may be an even bigger reason for concern.

"We're having 10 fewer crime reports each day for instances of domestic violence," Los Angeles Police Department Chief Michel Moore said. "That's going in the wrong direction with what we believe is actually happening behind closed doors."

Calls related to domestic violence in LA declined 18% from March 19 through April 15 compared with the same period in 2019, according to LAPD data provided to ABC News. Cases also declined in San Francisco.

Other cities including San Diego, Anaheim, Burbank and Santa Rosa have reported little change, while calls in Fresno County spiked in March but declined into April.

Nationwide, Philadelphia and Washington, D.C., reported lower overall violent crime numbers during stay-at-home orders, but it's unclear exactly how many of those were related to domestic violence.

In New York City, even with a record number of officers calling in sick during the COVID-19 outbreak in March, Commissioner Dermot Shea said "domestic violence is an extremely high priority for all members of the New York City Police Department."

Back in California, officials told ABC News they believe domestic violence is increasing but the abused are stuck at home with their abusers and can't alert authorities.

Rebecca Levenson, a police consultant on domestic violence, said that for victims their "world has gotten a whole lot smaller" and that they're "hyper vulnerable" because of technology.

"With home cameras, you literally can't do anything," she added. "The abuser can check which websites you were on and check your phone."

Police said that's resulted in fewer calls, which Los Angeles County is combatting with "Behind Closed Doors," a campaign aimed at helping abuse victims too scared to seek help.

Los Angeles Mayor Eric Garcetti announced a program this month to put domestic violence victims in hotels during shelter-in-place orders rather than return them to homes where they were abused. Garcetti highlighted the work of Rihanna and Twitter CEO Jack Dorsey, who have paid for hotels, food and counseling for victims of domestic abuse.

"I am very alarmed by what appears to be a dramatic decrease in reported crimes involving our most vulnerable," Los Angeles City Attorney Mike Feuer said on Friday.

Feuer and L.A. County District Attorney Jackie Lacey are leading the program that will put signs up in grocery stores and other places where abuse victims may see them to know they can reach out without their abuser knowing. One option might be texting 911 instead of calling.

The "Behind Closed Doors" campaign also is calling on delivery drivers, landscapers, postal workers and others in Los Angeles County who might see signs of abuse at homes to contact police.

"With this unprecedented situation," said Feuer, adding that children and the elderly also may be at risk, "there are some under-discussed consequences."

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