Possible Clues:

• Musical instrument that might have had a whistle?
• Exercised crowd control with peculiar instrument
• Herded by police, odd one that's given a beating
• Cook's equipment, initially damn funny source of rolls
• Lets off steam at department - that's the spirit you might play with when you're down in the pits
• Confined by police — suspect one soundly beaten?
• Kept in confined space, odd part of kitchen
• Like a mob being controlled with strange instrument
• King muttered vexedly holding learner instrument
• Boiler finally sounded odd - it's in the kitchen