text: The Perth club has suspended the team-mates pending a club investigation.
  Wright told BBC Scotland that "if what's alleged" to have occurred did in fact happen "we'll come down severely hard on both".
  Referee Don Robertson sent off both players during the break.
  Wright, whose side confirmed their top six place due to results elsewhere, says he did not see the incident as he had already started walking up the tunnel following the half time whistle.
  BBC Scotland reporter Jonathan Sutherland saw Foster throw a punch at Swanson, who retaliated by aiming a kick at the defender after he had slipped.
  "I haven't seen it with my own eyes but obviously something happened," said Wright.
  "I'm going to wait and see for myself. The players have been told they let themselves down, and let the team down. We should be celebrating confirming our top six place tonight.
  "Under no circumstance will they get off lightly if what is alleged to have happened has happened. The hardest punishment I can do legally with them, I'll do it."
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  Wright was angry that the incident left his side up against it in the second half, and that the shine was taken off the Saints confirming a top six berth.
  "It's another great achievement getting the top six," he added. "We showed a lot of character and should have had a penalty. (Georgios) Sarris has got arms all over Murray Davidson and that should have been a penalty kick.
  "The boys were magnificent and probably deserved a point but they didn't get it."
  Hamilton player Ali Crawford was shown a yellow card and assistant manager Guillaume Beuzelin sent to the stand after becoming involved in the chaotic scenes that followed the incident between Foster and Swanson.
  However, manager Martin Canning told BBC Scotland: "I would rather be talking about us. It is not something you want to see, but it is a passionate game and sometimes it spills over.
  "My players acted well. I think Darian MacKinnon was just trying to separate them and calm things down.
  "I don't think I have to take any action against my players."
  Hamilton moved off bottom spot in the table thanks to the win, sealed by a late Alex D'Acol goal. They are 11th on 27 points, two clear of bottom club Inverness Caledonian Thistle.
  "With 11 against 11 in the first half, I thought we were excellent and we kept going and got a huge three points," Canning added.
target: St Johnstone players Danny Swanson and Richard Foster are set to face "severe" punishments for brawling with each other in the 1-0 defeat at Hamilton, manager Tommy Wright says.