Hull City have signed Brighton forward Ryan Longman for an undisclosed fee plus Swansea midfielder Liam Walsh, Brentford striker Marcus Forss and Fenerbahce striker Allahyar Sayyadmanesh on loan.
Longman, 21, had been on loan with the Tigers and has now signed a three-and-a-half-year deal.
Forss, 22, Sayyadmanesh, 20, and Walsh, 24, have all joined until the end of the season.
Hull are 17th in the Championship.
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