Athens, Greece: Greece on Tuesday launched a multi-million euro auction for four private TV licences, a process originally due two decades ago and now marked by political infighting.

Eight groups are vying for the four 10-year nationwide licences, with opening bids starting at three million euros ($3.4 million).

Their representatives will be locked up in an office building with no outside communication until the process is complete, a move prompting angry protests from TV managers.

Authorities say they want to clean up an industry known for workforce exploitation and rumoured under-the-table deals between media moguls, bankers and influential politicians, while bringing an end to 25 years of chaotic licensing.

Government officials have noted that ever since private TV broadcasts began in Greece, channels have been allowed to operate on provisional licenses renewed 15 times since 1995.

And a contract for Greece's digital TV provider was concluded two years ago with just one contestant, they note.

But critics say the overhaul is merely a ploy by Prime Minister Alexis Tsipras to replace established TV barons -- who have opposed his leftist Syriza party in the past -- with others more to his liking.

- Mattress in tow -

Six of the eight groups participating in the auction have raised objections about the process.

The first private channel to hit the air in 1989, Mega, has already been eliminated from the tender over outstanding debts.

The first-ever tender is held under unprecedented security inside the state ministry of information in Athens.

The six-floor building was emptied of staff last week and bunk beds moved in for what looks to be a two-day process.

Rival TV representatives were shown arriving early Tuesday with luggage. One had a mattress in tow.

They are to be kept in complete isolation, and under closed-circuit TV surveillance, to prevent arranged bids. 

They are not to leave the building or communicate with the outside world until the process is concluded.

One TV manager called the conditions "humiliating" while another said stations were being "held to ransom".

Skai TV has sarcastically likened the procedure to reality TV show "Survivor".

Others have called it "Big Brother with TV chiefs".

Greece's top administrative court on Friday turned down a request by several of the channels to block the process.

The government has said stations that continue broadcast nationwide without a license will be blocked three months after the auction is concluded.