This is not a situation where different criminal offenses are involved rather there is but one offense and alternative bases of culpability for that offense. Finally, we find the Commonwealth's reliance on Commonwealthv. Ritchey, 313 Pa. Super. 238, 459 A.2d 828 (1983), and Commonwealth v. Ostolaza, 267 Pa. Super. 451, 406 A.2d 1128 (1979), to be misplaced. This court in both cases examined subsections of a criminal statute and found them not to represent lesser included offenses of one another.

Aggravated assault, § 2702(a)(4) is not a lesser included offense of aggravated assault, § 2702(a)(1). Commonwealth v. Ritchey, 313 Pa. Super. 238, 459 A.2d 828 (1983). If, upon a conviction or a plea, the court imposed a sentence relating to one subsection of the Crimes Code, when a different subsection carrying a different penalty was proved, this in effect would be an illegal sentence. This Court concludes on the basis of the charge in the information, the Commonwealth, by limiting the proof to causing or attempting to cause serious bodily injury to another, knowingly or recklessly, under circumstances manifesting extreme indifference to the value of human life, is bound by its charge and cannot go beyond the allegation in the information and proceed to offer proof of the use of a deadly weapon at sentencing.