With the January transfer window now open speculation is rife over potential deals involving Barclays Premier League sides, but Bruce insists recent reports about the Tigers' hunt for a striker have been wide of the mark.
There were suggestions earlier this week that Bruce had lodged a bid for Sunderland's Scotland international Fletcher, while the club issued a formal statement on Thursday morning dismissing reports that West Brom's Long - who was close to becoming a Hull player in September - was due in East Yorkshire for a medical after terms had been agreed.
Bruce is certainly interested in Long, who travelled to Hull by private jet on deadline day in the summer only for the Baggies to pull the plug, but insists there is nothing concrete as yet and is unhappy with inaccuracies being spread.
"First and foremost I really want to try and apologise to West Brom as a club, nothing has come from us and the same goes for another 'bid' for another striker. We haven't bid for anyone yet," he said.
"I don't mind speculation but I would be disappointed if I was manager of West Brom or Sunderland because it's simply not true.
"The way Twitter is, the way the media is it happens, but to be so far wide of the mark is ridiculous and it causes us a big problem because we've spent half the morning apologising to the respective clubs and we've got nothing to do with it.
"Two days before Long it was an £18million for Fletcher, another load of nonsense. What can I do but sit here and apologise to everyone concerned?"
Despite Bruce's frustration, he will surely be making contact before the window expires about Republic of Ireland international Long.
He was hugely frustrated when Albion pulled out of the deal last time and is still firmly in the market for a centre forward.
But the issue was muddied slightly by Tweets attributed to Long's wife Kayleah, suggesting he would not be leaving the midlands club.
In a message on her account she said "Not going anywhere! Told Shane happy here & with baby on way it not worth the stress when still in contract! He agreed?? £happydays."
Bruce added: "Make no mistake I'm not one for Twitter, it's not on my scene, but we'd all be lying if we said our wives didn't have an influence.
"But there's been a lot of talk about Shane because we were close in the summer.
"We have a couple of irons in the fire but at the moment we haven't made any bids for any players.
"The window's only been open a week so let's see how things develop in the next few weeks."
The only transfer activity so far at the KC Stadium has seen winger Cameron Stewart depart for Leeds, while Bruce remains open to offers for fringe men such as Aaron McLean, Nick Proschwitz, Gedo and Matty Fryatt.
Bruce, meanwhile, revealed that defender Paul McShane will be missing for up to a month after injuring his ankle in the FA Cup third round victory over Middlesbrough on Saturday.
"Paul is out for three to four weeks. He turned his ankle badly at Boro and he's not in the picture," he said.