A 45-year-old Gold Coast woman has been arrested inside a NSW brothel in connection with the murder of Brisbane rugby league referee Tony McGrath.

A woman has been arrested at a Sydney brothel in connection with the shooting murder of Brisbane rugby league referee Tony McGrath.

A friend found Mr McGrath’s body, with a single gunshot wound to the head, under his home in the suburb of Woolloongabba on May 21.

Mr McGrath had been appointed president of the Brisbane Rugby League Referees Association not long before his death.

NSW police on Friday arrested Susan Stewart, who is from Helensvale on the Gold Coast, inside a Brookvale brothel in Sydney’s north.

The 45-year-old woman faces a Queensland arrest warrant on one count of murder.

Queensland’s homicide investigation unit will seek her extradition from NSW on Monday when she faces Sydney’s Central Local Court.

Police describe Mr McGrath as a “loner” who had no family apart from his sister and say his lack of close relationships made it hard to track leads.

But after a nine month investigation officers on Wednesday arrested and charged a 43-year-old Coolangatta man.

Detectives searched a home in Terranora, NSW, and are speaking to a number of people believed to be linked to the investigation.

The man has been charged with murder, armed robbery, attempted murder or alternatively grievous bodily harm, arson, stupefying in order to commit indictable offence, entering a premises with intent and weapons offences.