In this Tuesday, Jan. 31, 2017 photo, a computer screen shows an archived copy of the Twitter feed belonging to Phineas Fisher, a hacker who claimed responsibility for breaching the union of the Mossos d'Esquadra, Catalonia's regional police, last year. Spanish police have arrested three people over a data breach linked to a series of dramatic intrusions at European spy software companies—feeding speculation that the net has closed on an online Robin Hood figure known as Phineas Fisher. (AP Photo/Raphael Satter)

Four people are being formally investigated in Spain on suspicion of breaking into a police union website last year, Catalonia's regional police said Thursday.

The force's announcement gave further detail on arrests that started a swirl of speculation over the fate of Phineas Fisher, a Robin Hood-like figure who has claimed responsibility for exposing state surveillance operations around the world and last year boasted of being behind the police union breach.

The announcement did little to clear up the key question of whether or not the net had closed on the notorious hacker, however.

A spokesman for the Catalan police force, known locally as Mossos d'Esquadra, said Thursday they had no evidence the four people under investigation were involved in the breaches of Italy's Hacking Team and Britain's Gama Group—both of which have supplied state-level cyberespionage tools and were allegedly breached by Phineas Fisher.

He stopped short of ruling out a connection.

The hacker—or someone acting in their name—denied having anything to do those under arrest.

"It's possible the people arrested retweeted or otherwise spread the leaked police info which might be a crime in Spain, or it's possible the police just arrested some random hacktivist-type people, I have no idea," the person told The Associated Press, adding: "My 'career' as Phineas Fisher is over, I just came back online to address the reports that Spanish police arrested me."

Authorities described the people in custody as information technology engineers. They said they had used the privacy-protecting network Tor to hide their tracks, but made a mistake that led investigators to them. The first arrested was a 33-year-old Spanish man in Salamanca who, according to the police, played a "secondary role" in the intrusion.

A man, 31, and a woman, 33, both Spaniards, were later arrested in Barcelona and are still being questioned. The fourth man, a Barcelona resident of Swiss nationality, turned himself in Thursday and was released, but will be required to appear before a judge.

It was unclear who if anyone was representing the unnamed suspects. Police did not provide the AP with information on their lawyers.

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