(a) Murder of the first degree.--A criminal homicide constitutes murder of the first degree when it is committed by an intentional killing.

(b) Murder of the second degree.--A criminal homicide constitutes murder of the second degree when it is committed while defendant was engaged as a principal or an accomplice in the perpetration of a felony.

(c) Murder of the third degree.--All other kinds of murder shall be murder of the third degree. Murder of the third degree is a felony of the first degree.

(d) Definitions.--As used in this section the following words and phrases shall have the meanings given to them in this subsection:

“Fireman.” Includes any employee or member of a municipal fire department or volunteer fire company.

“Hijacking.” Any unlawful or unauthorized seizure or exercise of control, by force or violence or threat of force or violence.

“Intentional killing.” Killing by means of poison, or by lying in wait, or by any other kind of willful, deliberate and premeditated killing.

“Perpetration of a felony.” The act of the defendant in engaging in or being an accomplice in the commission of, or an attempt to commit, or flight after committing, or attempting to commit robbery, rape, or deviate sexual intercourse by force or threat of force, arson, burglary or kidnapping.

“Principal.” A person who is the actor or perpetrator of the crime.