Turkey and Switzerland both face possible punishment following violent scenes after the final whistle of their World Cup playoff in Istanbul on Wednesday. FIFA's President Sepp Blatter has promised a tough stance from World football's governing body, after Turkey's World Cup playoff defeat by Switzerland finished in violence that left one Swiss player hospitalised.

"I can tell you this, not as a Swiss, but as the president of FIFA, that we will act here and we will act tough," Blatter told a news conference on Thursday, announcing an investigation into the incidents before and after Wednesday's playoff 2nd leg game in Istanbul.

"In the past few days, fair play has been trampled under foot, not just on the pitch but also outside. That hurts." Blatter, who described himself as “Hopping mad” added, “It (the inquiry) will show whether we will investigate against Switzerland, too.”

The FIFA inquiry could see punishment’s being handed out for both Turkey and Switzerland, which could range from a warning, to the full suspension of any football association found to be at fault. Sepp Blatter also said the investigation must be completed by December 9th, when the draw for the 2006 World Cup finals will be made in Leipzig, Germany, and includes Switzerland.

FIFA officials confirmed that Turkey, who got to the Semi-finals of the 2002 World Cup, have had two fines for crowd disturbances, plus two official warnings during their World Cup qualifying campaign, and have a history of crowd trouble at home matches.

Switzerland, who went into the match with a 2-0 lead from the first leg, reached the World Cup finals in Germany next year on the away goals rule, with an aggregate 4-4 scoreline, despite Turkey winning Wednesday's second leg in Istanbul 4-2.

Things started badly for the visitors on their arrival at Istanbul airport. The Switzerland squad was kept waiting for two hours at passport control and baggage reclaim. Police then struggled to hold back Turkish fans shouting abuse at the Swiss players, and the team bus was pelted with eggs.

After the match the visiting players left the pitch under a hail of objects thrown by the Turkish crowd, and then players from both sides clashed as they ran off the field for cover.

Switzerland defender Stephane Grichting needed hospital treatment after being kicked in the stomach in what became a free-for-all between the players in the tunnel after the match. Grichting was left neededing a catheter inserted, and will be out of action for up to 10 days.

"This was an experience I could have done without," Swiss captain Johann Vogel told reporters at a news conference in Zurich on their return to Switzerland, "I have never been scared on the pitch before."

The Swiss coach Koebi Kuhn said the Turkish security staff, who were there to protect the players, had joined in attacks on his team.

"Players, not just players, were beaten...they were thrown to the ground by security who should have been in charge of their safety," Kuhn said. "I hope this will be sanctioned but the matter is done for me. I am preparing for the World Cup now. But it is unforgivable that such things should happen."

But television pictures also showed Swiss player Benjamin Huggel kicking out at Turkey's assistant coach Mehmet Ozdilek as he was leaving the pitch.

In response Swiss coach Kuhn said; "Of course that happened but I can assure you that Huggel is a good man. He was provoked, he was beaten, he was defending another player."

"At the moment we're just questioning and we're questioning both sides because, of course, the Swiss want to justify themselves after what has happened."

Swiss midfielder Johann Lonfat backed up Kuhn’s claims of provocation, saying that the intimidation had gone beyond normal limits; "I was told, 'We're going to slit your throat'."

The Turks were quick to reply to the claims, with the Turkish Football Federation Chairman Levent Bicakci criticising Sepp Blatter's comments. "Our federation finds the FIFA president's statement really odd, and we will do whatever we can to clarify this event and to make sure Switzerland gets the same penalty as Turkey," he said.

The war of words intensified on Tuesday, when the Swiss foreign minister Micheline Calmy-Rey sent a letter of complaint to the Turkish government, calling the team's reception by Turkish fans in Istanbul as "unacceptable behaviour.”

The Turkish Football Federation then in turn protested that Swiss fans jeered their National anthem prior to the match in the first leg in Bern, and that the Turkish players had been verbally abused after Saturday's match. "The incidents in Switzerland put a Nation on edge...They exerted psychological pressure off the pitch," the Turkish Football Federation's Mosturoglu stated.