Four men, including a serving police officer, have been arrested in connection with Scotland Yard's investigation into payments to police officers by journalists. Police are also carrying out searches of the News International offices in Wapping, east London, and the homes of the four people. A 29-year-old serving police officer was arrested at his place of work in central London on suspicion of corruption and misconduct in public office. The officer, of the Met's territorial policing unit, is the second police officer to be arrested under the Operation Elveden investigation. A 48-year-old man and a 56-year-old man were arrested at their homes in Essex. Another man, aged 48, was held at his home in north London. All three were arrested on suspicion of corruption and aiding and abetting misconduct in public office. Scotland Yard said the arrests were made following information provided by News Corp's own investigation team. Rupert Murdoch set up the management and standards committee in July following the escalation of the phone-hacking scandal. According to well-placed sources, it has been conducting a forensic analysis of payments by all journalists between 2000 and 2006. A statement from the Met police said: "The arrests were made between 06.00 and 08.00 by officers from Operation Elveden, the MPS [Metropolitan police service] investigation into allegations of inappropriate payments to police. "The home addresses of those arrested are currently being searched, and officers are also carrying out a number of searches at the offices of News International in Wapping, east London. These searches are expected to conclude this afternoon. "Today's operation is the result of information provided to police by News Corporation's management and standards committee. It relates to suspected payments to police officers and is not about seeking journalists to reveal confidential sources in relation to information that has been obtained legitimately." All four men were being questioned at police stations in Essex and London, police said. Twelve people have so far been arrested under Operation Elveden. The operation is being supervised by the Independent Police Complaints Commission, and is being run in conjunction with Operation Weeting, the MPS inquiry into the phone hacking of voicemail boxes. It was launched after officers were handed documents suggesting that News International journalists made illegal payments to police officers. Others questioned as part of the inquiry include the former News International chief executive Rebekah Brooks, the ex-Downing Street communications chief Andy Coulson, the former News of the World managing editor Stuart Kuttner, the paper's former royal editor Clive Goodman, the former News of the World crime editor Lucy Panton and the Sun district editor, Jamie Pyatt. Brooks and Coulson are both former editors of the News of the World, which was closed in July at the height of the hacking scandal following revelations that the murdered teenager Milly Dowler's phone was hacked. Deborah Glass, the deputy chair of the Independent Police Complaints Commission, said: "It will be clear from today's events that this investigation is following the evidence. "I am satisfied with the strenuous efforts being made by this investigation to identify police officers who may have taken corrupt payments, and I believe the results will speak for themselves."