Two officials from Sporting Lisbon were arrested while the club's players were still reeling from being physically attacked by fans at a training session.
The corruption arrests followed a Judicial Police swoop on Sporting Lisbon's club headquarters in Alvalade here on Wednesday, reports Xinhua news agency.
According to the Correio da Manha newspaper, the arrests relate to an alleged corruption scheme whereby referees were bribed to favour Sporting Lisbon in handball games.
The newspaper reported that the investigation, code-named "Cashball", is also looking into underhand payments related to six football matches.
Sporting Lisbon is best known for its football team. But it also has high-profile teams in several other sports, including handball, basketball, indoor football and roller-hockey.
Meanwhile, 23 Sporting Lisbon supporters appeared before the Criminal Court of Barreiro, a town across the River Tagus from Lisbon, accused of assaulting the club's footballers.
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Some 50 people broke into Sporting Lisbon's training complex in Alcochete, in the Barreiro district, on Tuesday and attacked a number of Sporting Lisbon footballers.
The players were preparing for a training session ahead of Portugal's Cup Final on Sunday in which Sporting Lisbon face Desportivo das Aves.
The intruders, who claimed to be fans and all had their faces covered, ran across the training pitches and entered the changing rooms, where they allegedly verbally and physically abused players and coaching staff.
Some sources claim players were slapped, punched and headbutted.
The attackers were said to be protesting Sporting Lisbon's poor performance in the final game of the league season on Sunday.
A 1-2 defeat to Maritimo meant that Sporting Lisbon finished third in the championship, one place below their city rivals Benfica, and thus missed out on qualification for the Champions League.
The club have said that the players still intend to play in the cup final on Sunday although they are in a state of shock.
--IANS
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