Section 43A. (a) Whoever willfully and maliciously engages in a knowing pattern of conduct or series of acts over a period of time directed at a specific person, which seriously alarms that person and would cause a reasonable person to suffer substantial emotional distress, shall be guilty of the crime of criminal harassment and shall be punished by imprisonment in a house of correction for not more than 21/2 years or by a fine of not more than $1,000, or by both such fine and imprisonment. The conduct or acts described in this paragraph shall include, but not be limited to, conduct or acts conducted by mail or by use of a telephonic or telecommunication device or electronic communication device including, but not limited to, any device that transfers signs, signals, writing, images, sounds, data or intelligence of any nature transmitted in whole or in part by a wire, radio, electromagnetic, photo-electronic or photo-optical system, including, but not limited to, electronic mail, internet communications, instant messages or facsimile communications.