Nicola Brookes, 45, from Brighton was targeted earlier this year after expressing support on Facebook for a contestant on the X Factor TV show, Frankie Cocozza, after he had received abusive messages on the service.
After posting the message, "keep your chin up, Frankie, they'll move on to someone else soon," Brookes herself became the target of a campaign, receiving abusive comments.
The bullies then set up fake Facebook profiles in her name from which they sent explicit comments to other Facebook users. She was also allegedly described as a drug user, prostitute and child abuser by attackers before having her home address published.
After complaining about the abuse, ordering Facebook to reveal the names, email addresses and IP addresses which led to the arrest.
"The abuse is absolutely horrendous and nothing can be done about it and nothing can be stopped," she said. "I am not going to give up until these people are found, exposed and held accountable for what they have done," Brookes told the BBC at the time.
The police are still investigating whether Brookes's Facebook account PC was illegally accessed by the attackers but released a statement confirming the arrest of a suspect.
"The investigation is ongoing by Sussex police, and the allegations do not relate to use of police systems. The officer has not been suspended. The officer is not a frontline officer," The Guardian reported a spokesman for the West Midlands force as saying.
The issue of Internet trolls, especially inside closed services such as Facebook and Twitter, has become increasingly contentious over time.
Part of the would force services to reveal the IP addresses and names of so-called trolls more quickly than at present.