It's unclear why police arrested four BBC journalists at the weekend. They were supposedly investigating the activities of dissident Irish republicans, and were held under section 30 of the Republic's Offences Against the State Act. All four have now been released without charge. Film was also seized by the police, but it is not known whether that has been returned.
The journalists were detained in Donegal along with seven men suspected of being involved in paramilitary activity on behalf of the so-called Real IRA. According to a BBC statement, the journalists were working on a BBC Northern Ireland current affairs investigation "and had full editorial authorisation under the BBC's guidelines."
I took that to mean that they were working for Spotlight, BBC Northern Ireland's flagship investigative current affairs programme, a hunch confirmed by Henry McDonald's report that reporters and researchers working for Spotlight "were meeting leading figures connected to the Real IRA" when detained.
But a report in the Irish Independent, suggested that there were two separate BBC teams. One was investigating the murder of a senior Sinn Fein member Denis Donaldson, who was killed two years ago in Donegal after admitting that he spied for the British authorities. The other was investigating diesel-laundering and smuggling for Panorama.
More later.