NORTON SHORES, Mich. (WZZM) -- Police and investigators have received hundreds of tips about the Jessica Heeringa case from people all over West Michigan, and in some cases, the world.

Norton Shores Police Chief Daniel Shaw says his department has received over 500 tips. "There have been people looking at home, doing their own investigation for us then providing that information," says Shaw.

Most of those tips coming in have been grey or silver van sightings from people writing down plate numbers then phoning it in, but there are some tips coming in from web sleuths. Tipsters have been visiting criminal internet databases and comparing photos with the sketch of the suspect. There are even people scanning Google maps.

"I have reports of someone looking at Google Maps and if you blow the map up from a birds eye view, you can see a grey or silver mini van," says Shaw. Shaw points out that those maps in some cases go back to 2009, so they may not be that accurate, but he still wants those tips.

"I have said from the start we need any and all information, so we appreciate all of that, but we do have to prioritize the information that we get," says Shaw.

In other words, not every tip is given equal treatment.

If you end up seeing or hearing something, the best thing you can do is contact police or Silent Observer. What you shouldn't do is post it on Facebook.

"The suspect or the person of interest may have access to that Facebook page," says Shaw.

Also, if you see a grey or silver van Shaw says, "I would just caution the public not to get involved in road rage type incidents or do anything illegal while they are trying to chase down some license plate.

In the end, Shaw thinks the citizen investigators are doing a good job and should keep sending in tips.