Sergeant Jason Dance, who leads the western region division two family violence investigation team, said a third-party report containing "very vague" information about the victim's welfare was the tip of the iceberg in uncovering the alleged terrifying and protracted family violence she endured.

Sergeant Dance said the victim would still be locked behind closed doors if not for the "small and indistinct piece of information" which he could not detail because the case remained active.

He said the incident was one of many uncovered during Operation Ribbon, a state-wide campaign aimed at keeping family violence perpetrators in sight during the coronavirus pandemic.

Since the operation's inception in March, detectives and frontline officers have uncovered more than 5000 domestic violence offences across the state, including assaults and breaches of intervention orders.

Sergeant Dance said south-west detectives were checking more than 100 homes per month across western region division two division, which takes in the Warrnambool, Moyne, Southern Grampians, Corangamite and Glenelg local government areas.

There were 41 checks this week alone, he said.

He said detectives and frontline officers were targeting both recidivist offenders and known, vulnerable victim-survivors.

"We act on that using our own intelligence but also intelligence that the public may provide us," Sergeant Dance said.

"By reaching out to those people, we've been able to remove a number of women from very dangerous situations, including women that have been really seriously assaulted."

Sergeant Dance, who reads the narrative of every single family violence case throughout the region, said Operation Ribbon had also identified women, families and perpetrators he'd never heard of.

He said coronavirus restrictions had changed the triggers of violence in the home and families were experiencing police involvement for the first time.

"We are seeing a lot more frustrations towards being in lockdown, financial difficulties, tensions are rising and members of the family are irritable," he said.

"In some cases you've also got additional vulnerabilities such as mental health, drug use, alcoholism, and pressure from the kids and homeschooling.

"All of these combined are affecting the way family violence is coming about."

Sergeant Dance said for the known victim-survivors, it was increasingly difficult to report violence during the pandemic.

"There's been an overall drop in reporting because people haven't been able to get out of the house and that's why the proactive police involved in Operation Ribbon is so important," he said.

"If we can locate these women, we can proactively check on their homes and in some cases it's been really, really clear that they've been seriously assaulted and we've been able to take immediate action (such as making an arrest).

"Unfortunately it's not always clear and that's where the results are tangible. Sometimes we perceive a risk and we try our best to mitigate that through intervention orders or other avenues.

"It doesn't always result in an arrest but it certainly results in affirmative action where we can increase the safety around that woman and increase offender accountability."

Sergeant Dance is one of five detectives stationed at the family violence investigation unit which was started in October 2018.

He said it was the feeling of hopelessness when "you see someone beaten black and blue, terrified of every waking minute with their partner" that motivated him to keep doing more.

"In all good consciousness, you can not do anything but everything for that person," he said.

"It's just about protecting people and that's why we all join the police force."

But Sergeant Dance said family violence was also "everyone's responsibility".

"As restrictions ease, community visibility on victims is increased and that's when you see those hidden injuries, the change in behaviour, and those little things that indicate something is not right," he said.

"It might be something as obvious as visible or unexplained injuries, or it could be a change in behaviour - a friend becoming withdrawn, frightened or not able to spend money without the permission of their partner.

"If you're concerned, say something. Offer help, call police or a welfare agency or ask that person what is going on because family violence is everyone's responsibility, it's not just police responsibility."

Warrnambool police Acting Inspector Brett Jackson said third-party reporting was vital to uncovering family violence offending during Operation Ribbon.

"One small piece of information might not seem that important to a concerned family member or friend but for our detectives it could be the tip of the iceberg in uncovering serious violence in the home," he said.

"Even the most minor piece of information will be treated as significant and it will be investigated as thoroughly as possible.

"Detectives like (Sergeant Dance) can and will pick up any little signs that might be insignificant to the member of the public but mean a lot more to him.

"You can tell from the way (Sergeant Dance) speaks to it - the passion, experience, skill and dedication to family violence, not only for his unit but for all of Victoria Police, is a big priority for us."

Family Violence investigation and response manager Detective Senior Sergeant David Reither said police were available 24/7 during the pandemic and beyond.

"While restrictions are now beginning to ease, not everyone will be comfortable to go out and we urge concerned friends and family members to make those third-party reports," he said.

"If you notice someone is being controlled emotionally, physically or financially, get that information across to us so that we can help.

"There's been a few arrests that we would not have known about if not for that third-party reporting."

You can make an anonymous report to Victoria Police or Crime Stoppers.

If you or someone you know is impacted by sexual assault, domestic or family violence, call 1800RESPECT on 1800 737 732 or visit 1800RESPECT.org.au. In an emergency, call 000.

Emma House is a Warrnambool-based not-for-profit service and can be contacted through 1800 EMMADV (1800 366238) or visit emmahouse.org.au/

Safe Steps for women after hours service is available through 188 015 188.

Brophy Family and Youth Services can be contacted on 1300 BROPHY or 03 5561 8888.

Have you signed up to The Standard's daily newsletter and breaking news emails? You can register below and make sure you are up to date with everything that's happening in the south-west.