Lancashire Police have referred themselves to the UK police watchdog over contact the force had with missing mother Nicola Bulley prior to her disappearance.
The Independent Office for Police Conduct (IOPC) said it was assessing the information to determine whether an investigation would be necessary over the contact officers had with the missing mother-of-two on 10 January.
The referral comes after Ms Bulley's family called for an end to the "speculation and rumours" about her private life.
Police were criticised for disclosing that she suffered "some significant issues with alcohol" in the past, which had resurfaced over recent months.
Senior officers said yesterday that Ms Bulley was "vulnerable" and classed by police as a "high-risk" missing person immediately after her partner Paul Ansell reported her disappearance.
Confirming a referral had been made to the watchdog, a spokesman for the IOPC said: "This afternoon we received a referral from Lancashire Constabulary regarding contact the force had with Nicola Bulley on January 10, prior to her disappearance.
"We are assessing the available information to determine whether an investigation into that contact may be required and if so, who should conduct that investigation."
In a statement issued through the force today, Ms Bulley’s family said: "We, as a family, believe that the public focus has become distracted from finding Nikki, and more about speculation and rumours into her and Paul’s private life.
"As a family, we were aware beforehand that Lancashire Police, last night, released a statement with some personal details about our Nikki.
"Although we know that Nikki would not have wanted this, there are people out there speculating and threatening to sell stories about her. This is appalling and needs to stop."
A Home Office spokesperson said: "Our thoughts are with Nicola Bulley's family at this incredibly difficult time.
"The Home Secretary and Policing Minister are receiving regular updates from Lancashire Police on its handling of this case, including why personal details about Nicola was briefed out at this stage of the investigation."
Ms Bulley vanished after dropping off her daughters, aged six and nine, at school on 27 January in St Michael's on Wyre, Lancashire.

She was last seen at 9.10am taking her usual route with her springer spaniel Willow, alongside the River Wyre.
Her phone, still connected to a work call for her job as a mortgage adviser, was found just over 20 minutes later on a bench overlooking the riverbank, with her dog running loose.
"The police know the truth about Nikki and now the public need to focus on finding her," the statement said.
After the force revealed her issues with alcohol "brought on by her ongoing struggles with the menopause", the force was strongly condemned by MPs and campaign groups.
Ms Bulley's family said significant side effects of the perimenopause she suffered included brain fog.
Their statement continued: "Due to the perimenopause Nikki suffered with significant side effects such as brain fog, restless sleep and was taking HRT to help, but this was giving her intense headaches, which caused Nikki to stop taking the HRT thinking that may have helped her but only ended up causing this crisis.
"The public focus has to be on finding her and not making up wild theories about her personal life.
"Despite what some media outlets and individuals are suggesting, we are being updated daily and receive support from our family liaison officers.
"Nikki is such a wonderful daughter, sister, partner and mother and is missed dearly – we all need you back in our lives.
"Nikki, we hope you are reading this and know that we love you so much and your girls want a cuddle. We all need you home.
"You can reach out to us, or you can contact MissingPeople.org.uk. Don’t be scared, we all love you so very much."
Concluding their statement, Ms Bulley's family issued a direct plea for her to return, saying: "Your girls want a cuddle."

Ms Bulley's parents, 73-year-old Ernest and Dot Bulley, 72, left a yellow ribbon tied to the bridge over the River Wyre, where their daughter vanished.
Among other ribbons left by friends and well-wishers, the message from Ms Bulley’s parents read: "We pray every day for you. Love you, Mum + Dad XXX."
A second ribbon, believed to be from Ms Bulley’s sister, Louise Cunningham, read: "Nikki please come home. I love you. Lou XXX".
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Nicola Bulley case: What is focus of police investigation?