leeds fans , kevin speight and christopher loftus , were killed before the uefa cup semi-final first leg against galatasaray in istanbul in april 2000 .
leeds are marking 15th anniversary with a minute 's silence on saturday .
wesley sneijder tweeted on the morning of the match : ` finally my galatasaraysk knife set is now available and can be delivered everywhere '
the striker later deleted the tweet after receiving angry responses .
sneijder replied to one supporter : ` very sorry . i did n't know this and deleted our promotion for the merchandise kitchen item . #respect '