London police said on Thursday they had arrested a fourth person as part of their new investigation into a phone-hacking scandal at a top-selling newspaper belonging to Rupert Murdoch's News Corp group.
The 39-year-old woman was taken into custody shortly before 7 a.m. (2 a.m. EDT) at a house in West Yorkshire in northern England on suspicion of conspiring to intercept voicemail messages, police said in a statement.
Detectives are investigating assertions that journalists on the News of the World tabloid hacked the phones of members of the royal family, politicians, celebrities and sports stars to listen to their voicemail messages.
The scandal dates back to 2005-6 when the News of the World's royal reporter and a private detective were arrested and later jailed for snooping on the voicemail messages of royal aides.
Police launched a new inquiry last January after being severely criticized over their original investigation, which critics said had not gone far enough.
News International, parent company of the News of the World, said in April it would admit liability and pay compensation in eight cases, though many more people believe they were targeted.
In April, detectives arrested the paper's chief reporter Neville Thurlbeck, one of its senior reporters James Weatherup, and Ian Edmondson, a former senior editor who was sacked after an internal inquiry into his conduct. Both were freed on bail after questioning.
"This morning's events did not relate to a current employee or a former full time member of staff of the News of the World," News International said in a statement.
"We have been cooperating fully with the police inquiry since our voluntary disclosure of evidence reopened the police investigation."
Dozens of high-profile figures including Hollywood star Jude Law are now suing the newspaper for allegedly trawling their phone messages for salacious details to sell to newspapers.
Earlier this month film star Sienna Miller's privacy and harassment claim against the paper was settled for 100,000 pounds and lawyers say the company could face claims which could cost it 40 million pounds ($65 million).
The issue has also affected Prime Minister David Cameron, whose former media chief, Andy Coulson, was the paper's editor when the hacking scandal broke.
Coulson later resigned his government post, although he always denied any knowledge of the practice.