A private security team was hired to follow and photograph a Reuters special correspondent who has written a series of articles exposing mismanagement in Greek banks.

Stephen Grey, who was in Athens last week for further reporting, was followed to a meeting at a building in the city on June 20.

The unidentified watcher waited for an hour and a half until Grey emerged. He then followed Grey to the Reuters office in Syntagma Square in the city centre, where the watcher was joined by a second man who arrived on a motorbike.

The two men kept the office under observation for more than an hour, Reuters security staff said.

That evening, Grey held a meeting in the garden of a hotel with two people, one of whom was Tassos Telloglou, a Greek investigative journalist.

As they were talking, a man entered the hotel, made his way to the rear and attempted to take a picture of Grey and his companions through a window. Telloglou noticed the photographer and chased him through the hotel and foyer. When Telloglou caught up with him, the man said he had been paid to track Grey.

He provided the name of an unlicensed private security firm which, he said, had organised the work and was paying him 100 euros per day. It was not clear who had commissioned the security firm.

Grey and Telloglou reported the incident to Greek police.

The man who tailed Grey at the hotel also said his firm was involved in taking photographs of Grey, Telloglou and Nikolas Leontopoulos - a freelance journalist working for Reuters on the investigation into banks - when they had previously met at a private hospital.

"You have no idea how much we've been doing,» the man told Telloglou. The photographs from the hospital were passed to Greek blogs.

This year, Reuters has published investigations led by Grey into two banks in Greece - Proton and Piraeus - and Marfin Popular Bank in Cyprus, which has a major branch in Greece. Marfin has now been renamed Cyprus Popular Bank.

Piraeus, one of Greece's biggest banks, has filed a lawsuit against Reuters, claiming 50 million euros ($62 million) in damages after Reuters published a report about a series of property deals between the bank and companies run by the family of its executive chairman.

Asked whether it had commissioned any surveillance of Grey, a spokesman for Piraeus said the bank «considers the question and its implication insulting and possibly defamatory and, given that we are already engaged in formal legal proceedings against Thomson Reuters, declines to comment further."

Spokesmen for the former management of Marfin and for the former management of Proton, both of which were the focus of stories, denied any involvement in the surveillance. [Reuters]