Warnock was furious after Gary Kelly's late tackle on Blades defender Craig Short just before the break.
The promoted Blades were ahead after just 10 minutes as Eirik Bakke headed an own goal past Neil Sullivan.
But Leeds levelled through David Healy's brilliant left-foot strike three minutes before the break.
Leeds boss Kevin Blackwell:
"There was some passion in it, that's for sure, and if anyone thought either side was just going to give it up they were sadly mistaken.
"There was no way Sheffield United were going to make it a showboating occasion and some of the tackles showed that.
"We've come away unbeaten again and that's four games against Reading and United this season and we've yet to lose. That's a positive. We had good possession of the ball and it was a solid performance."
Sheff Utd: Kenny, Short, Unsworth, Geary, Lucketti, Jagielka, Kabba (Dyer 82), Montgomery (Armstrong 60), Tonge, Akinbiyi, Webber (Ifill 79).
Subs Not Used: Morgan, Shipperley.
Goals: Bakke 10 og.
Leeds: Sullivan, Kelly, Crainey, Butler, Kilgallon, Miller, Bakke (Pugh 80), Derry, Hulse, Douglas, Healy (Moore 79).
Subs Not Used: Bennett, Beckford, Graham. Booked: Crainey, Kelly, Miller, Derry.
Goals: Healy 42.
Ref: G Poll (Hertfordshire).