The RUC Chief Constable, Sir Ronnie Flanagan, last night said he could not rule out the possibility that the Provisional IRA had murdered Mr Joe Joe O'Connell, who was shot dead in Belfast last month. Sir Ronnie said the RUC was following this line of inquiry. Earlier the Chief Constable rejected a request from SDLP and Sinn Fein members of Derry City Council to take down a watch tower at the RUC's station in the Rosemount area.