I have an auto insurance policy # for the person who hit my property. How do I find which company issued it?

The police report shows an insurance policy number, but it does not state the name of the issuing company. The person ran into my brick and iron fence with his car and I want to file a claim against his insurance (not my homeowner's policy). The police apparently do not record this information (annoying). Is there a numerical format of some kind that easily identify's which company issued the insurance?