Ian Edmondson and Neville Thurlbeck were arrested on Tuesday on suspicion of hacking into voicemail messages (Images: Phil Adams, Rex; Peter Jordan, PA)

A former News of the World senior executive and the tabloid's current chief reporter have been arrested on suspicion of unlawfully intercepting voicemail messages.

The Metropolitan Police said in a statement on Tuesday that two men had been arrested after separately attending police stations in London. Police did not name the individuals, but they have subsequently been identified as Ian Edmondson, 42, and Neville Thurlbeck, 50.

"They remain in custody for questioning after being arrested on suspicion of conspiring to intercept communications, contrary to Section 1(1) Criminal Law Act 1977, and unlawful interception of voicemail messages, contrary to Section 1 RIPA 2000," the Met said.

The arrests were made under the auspices of Operation Weeting, the current police investigation into phone hacking at the News of the World. The probe was set up to examine evidence relating to the phone-hacking scandal and assess whether there were sufficient grounds for new charges to be laid.

Both men have denied involvement in illegal activities while working for the tabloid.

Edmondson was the News of the World's assistant news editor until January this year. He was fired by the paper's publisher, News International, after an internal investigation led to the discovery of a series of emails implicating him in illegal phone hacking.

Thurlbeck, whose name has previously been mentioned in connection with the scandal, remains at the paper as its chief reporter. The Met's assistant commissioner John Yates admitted before MPs last September that it was a mistake not to interview Thurlbeck as part of the original police probe into phone hacking allegations in 2006.

Police only interviewed one News of the World journalist, the former royal editor Clive Goodman, during the initial investigation. Goodman was jailed alongside the private investigator Glenn Mulcaire in 2007 for intercepting the voicemail messages of members of the royal household.

The phone-hacking scandal has escalated dramatically over the past year, and the News of the World is now the target of a string of civil cases brought by celebrities and other public figures. Those civil cases brought about the disclosure of information that appeared to confirm suspicions that the extent of illegal practices at the tabloid was far wider than the 2006 police investigation had uncovered.

The floodgates could be opened further after a High Court judge ruled on Friday that litigants should have access to an archive containing millions of internal emails, some of which may shed light on the number and identities of potential victims.

"We continue to co-operate fully with the ongoing police investigation," News International said in a statement after news of the arrests broke.

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