A Panathinaikos water polo official was briefly held in custody on Sunday in connection to violent scenes during his team's encounter with Olympiakos on Saturday that led to several people being injured.

Nikos Plytas, an administrative official for Panathinaikos, was released from custody after being questioned in connection with the incident at Halandri swimming pool. It is believed that he has not been charged.

Tension had been running high throughout the match and things got worse when Olympiakos coach Vangelis Pateras was struck by an object on the head towards the end of the game.

This led to him exchanging words with some Panathinaikos fans and Plytas. The referees sent Plytas to the stands for his behaviour.

At the end of the game, which Olympiakos won 11-6, about 100 Panathinaikos fans started throwing all kinds of objects at the opposition players, who were also physically attacked.

In scenes that have rarely been seen at a water polo match, the brawl spilled out onto Pendelis Avenue. The eight policemen at the game were unable to restore order and two squads of riot police were called in.

The result of the clash was Pateras needing 10 stitches for a head wound and Olympiakos player Giorgos Daskas suffering a serious bruising to his leg after being struck with an iron bar.

"We could have been mourning victims," said Daskas.

Olympiakos captain Thodoris Hadzitheodorou suggested that the return match should be cancelled for fear of reprisals

The Piraeus club have threatened legal action against Panathinaikos and are pushing for the location of the upcoming women's volleyball match between the two clubs to be changed.

From Panathinaikos's side, Plytas condemned the violence but claimed that some Olympiakos players and officials had provoked the fans.

Halandri Municipality appears set to stop hosting water polo matches at the local pool.

It remains to be seen if Panathinaikos will be punished for Saturday's events.