(a) The person commits the crime of bail jumping in the first degree if, having been lawfully released from custody, with or without bail, upon condition that he will subsequently appear at a specified time and place in connection with a charge of his having committed murder or any Class A or B felony, he fails to appear at the time and place.
(b) It is a defense to prosecution under this section that the defendant's failure to appear was unintentional or was unavoidable and due to circumstances beyond his control. The burden of injecting the defense of an unintentional failure to appear, or unavoidability and circumstances beyond his control, is on the defendant.
(c) Bail jumping in the first degree is a Class C felony.