Nathan Charles Greiwe ran away yesterday and has authorities concerned.  

Authorities are being very cautious with the search as they believe he stole his grandfather's handgun and some ammunition. The former Lake Orion student caused all school activities in Lake Orion to be canceled for safety concerns.

Apparently, Greiwe mentioned to school leaders that he was going to try out for football. Now, all activities are cancelled and police urge you to call 911 if you see him.

Here is the post on the Lake Orion Community School's Facebook page:

Source: clickondetroit.com