Town extended the unbeaten home run to 14 games with goals from Pablo Counago, Jon Walters and a penalty from Alan Lee giving Blues a comfortable win.
Counago opened the scoring with a close range finish on 19 minutes after good work by Danny Haynes, the Spaniard taking his tally to nine for the season.
Iain Hume levelled the scores soon after with the Foxes' only effort on goal but Town regained the lead with a controversial penalty on 39 minutes, Patrick Kisnorbo judged to have brought down Counago in the box.
Referee Phil Joslin consulted his assistant before pointing to the spot, inflaming the Foxes who protested long and hard. Kisnorbo then shown a red card, igniting more protests.
Lee, who missed from the spot against Charlton on Saturday, stepped up to send the ball past Fulop.
It was one way traffic after the goal with Walters grabbing a third just past the hour mark.
Shane Supple and Tommy Miller were pulled out of the squad after suffering a bug in the morning. Sito kept his place at full-back, Dan Harding dropping out.
Haynes was handed a first start of the season on the right flank with Academy scholar Jordan Rhodes on the bench for the first time.
Walters had the first shot of note, Marton Fulop coping comfortably with the strike, the Leicester 'keeper then dealing with an Alan Lee cross.
Haynes and Owen Garvan combined to set up a crossing chance for Haynes, Kisnorbo in the right place to clear at the near post.
Fulop was then quickly off his line to smother from Counago, who carried the main threat for Blues.
Leicester's first shot came on 18 minutes when teenager Andy King pulled the ball wide from the edge of the box.
A minute later, Blues were ahead, Haynes' pace too much for Joe Mattock and his cross was controlled and then volleyed in by Counago.
Leicester responded with a tame header from Hume, while at the other end Gareth McAuley cleared from Counago as the Spaniard threatened.
Town had a penalty appeal on 25 minutes with Walters claiming he had been tugged back but referee Phil Joslin waved away the shouts and seconds later Leicester were level, Hume lifting the ball over Alexander after Stephen Clemence's header forward.
Clemence shot wide as Leicester pressed, Matty Fryatt central to their attacking threat.
Counago should have put Blues in front on 33 minutes, heading David Wright's cross wide from six yards, then Fulop saved low from Haynes' cross.
The game exploded six minutes before the break when Kisnorbo was judged to have fouled Counago in the box, the Australian sent-off after heated protests, Lee scoring from the spot.
Haynes should have made it three just before the break, the England U19 international thwarted as he tried to round Fulop.
Leicester made one change at the break, James Chambers replacing Alan Sheehan.
Garvan's shot was blocked after a great cross by Sito, then Jason De Vos fired over the bar from the edge of the area after stretching for Gavin Williams' pass.
Haynes was denied by Bruno N'gotty's tackle inside the box as Blues forced the Foxes back.
De Vos bravely blocked from Hume after Fryatt's knockdown, with Walters getting in front of Chambers to head just wide.
Wright was denied his third goal for the Club after his shot was deflected wide by desperate Leicester defending, McAuley than hacking Haynes' cross clear.
Walters made it three on 64 minutes, placing the ball into the net from a Wright cross as Town's pressure started to tell. Chambers booked for a foul on Counago.
The Foxes made two changes on 72 minutes, Jon Hayes and Collins John on for Hume and King. Fulop immediately saving well from Lee, Haynes' shot on the rebound going in the sidenetting.
Counago then set up Garvan on the edge of the box, the Irishman trying a slide rule finish but Fulop saving comfortably.
Liam Trotter replaced Walters for the last 10 minutes and the midfielder set up Counago for a tap in on 89 minutes after taking a pass from fellow substitute Billy Clarke but Fulop denied the striker with an excellent save.
Town: Alexander, Wright, De Vos, Wilnis, Sito, Haynes, Williams, Garvan, Walters (Trotter 80), Lee (Clarke 89), Counago. Subs not used: Legwinski, Casement, Rhodes.
Leicester: Fulop, N'Gotty, Kisnorbo, McAuley, Mattock, Kaebi, Clemence, King (Hayes 72), Sheehan (J.Chambers 46), Fryatt, Hume (John 72). Subs not used: Henderson, Cort. Sent-off: Kisnorbo. Booked: Chambers.
Att: 17, 938



















