Sandy Hook killer's psychiatrist who worked for Waikato DHB arrested in US

Adam Lanza fatally shot 20 children aged between 6 and 7 years old, as well as six adult staff members at Sandy Hook Elementary School in 2012.

The former psychiatrist who treated the Sandy Hook shooter, Adam Lanza, before moving to New Zealand has been arrested in his hometown in the United States.

Paul Fox, who was employed by the Waikato District Health Board in 2012, was arrested at his home in Peaks Island, Maine, on April 20 in relation to an alleged sexual relationship with a former patient.

US media have reported the woman, aged 18 or 19 at the time, claimed she'd had sex with him in his office, they'd gone out for dinner together and spent time on his boat.

It is the same allegation that led to him voluntarily surrendering his US psychiatry licence and that later led to public scrutiny over his credibility in New Zealand.

Despite his voluntary surrender of his licence Mr Fox maintained "no guilt or wrongdoing" in an affidavit.

In 2014 the Herald revealed the allegations against the psychiatrist, who had been working in Hamilton since June 2012.

He began work as a locum in 2012 before being signed on as a full-time employee with the DHB's mental health and addictions service.

At the time the allegations were revealed, the DHB confirmed Dr Fox had been fully registered and had the credentials to practise in New Zealand and was a "competent psychiatrist and good addition to the mental health team".

It appeared he had told his Kiwi employers that he had voluntarily surrendered his medical licence in the United States, but it was not clear if he had disclosed the details of the allegations against him.

An internal investigation over his actions was undertaken.

The Waikato District Health Board confirmed Dr Fox had ceased working for it in January 2014, but refused to divulge further details.

A spokeswoman said no further comment would be made, following the news of his arrest.

US media reported that Dr Fox had treated the gunman behind the December 2012 mass shooting at the Sandy Hook Elementary School. Twenty-six people died in what has been labelled as the second-worst school shooting in US history.

US authorities raised no concerns over his treatment of the shooter, Adam Lanza, but unveiled the details of his interactions with his female patient through the course of their investigations.

The investigation report said his interactions with the woman, "exceeded the boundaries of a professional doctor-patient relationship".