The public is encouraged to call the Norton Shores Police Department at 231-733-2691 or Silent Observer at 231-72-CRIME (231-722-7463).
A $15,160 reward remains in place to aid in the investigation.
To make a donation to the reward fund, make out a check or money order to the Community Foundation of Muskegon County, c/o Silent Observer. Donations should be mailed or dropped off at the Norton Shores Police Department, 4814 S. Henry St., Norton Shores, MI 49441.
Donations can be made directly to Silent Observer; or, if you would like your donation returned if not used, mark “Reward for Jessica” on it.
Heeringa, 25, disappeared from the Exxon Station at 1196 E. Sternberg Road in Norton Shores in late April.