Ivo Leitans, a reporter for LTV's De Facto investigative show and the current chairman of the Latvian Journalists' Association, revealed via Twitter that he had "joined the Security Police visitors' club" after being summoned to the DP's Riga headqurters.
The summons was apparently linked to a report dating from July 2016 in which Leitans reported allegations by a former anti-corruption official that he had been offered huge bribes in connection with a high-profile case involving former management at state-owned Latvian Railways.
Though he was not asked directly to reveal his sources, Leitans said he gained the impression investigators were trying to establish whether the sources named in his report were his real sources.
The DP investigation was based on part of the legal code concerned with "deliberate disclosure of state secrets", he added.
"I don't face any charges. As I understood, the investigator has to formally ask me if the things that were broadcast were really told to me in person," Leitans told LSM.
He had decided to make his visit to the DP HQ public immediately because it was likely that at some future point he would be made to sign a non-disclosure agreement forbidding him to mention the case, though so far he had signed nothing, Leitans said.
"Hello! I've joined the Security Police-goers club. I've been asked to testify about the following story of mine," tweeted Leitāns.
Labdien! Es arī pievienojos uz Drošības policijas gājēju klubiņam. Esmu uzaicināts liecināt par šo savu sižetu https://t.co/y3G8FO1XzT
— Ivo Leitāns (@ivchix) February 10, 2017
Nor is Leitans the only journalist to be called to the Security Police in connection with the case. Indra Sprance of the Ir weekly news magazine said February 9 she had made the same trip last year and "politely explained" that she would not reveal her sources.