You need to contact the Police so You can be eliminated.

Others may come forward telling of 2 Mercs together, then the Police will be looking for the Other Merc (you?) to eliminate you from enquiries.
Unless you were more involved than you say in which case they will find you anyway, as you have posted here.

For the Mail drivers back to be broken the Merc must have been moving pretty quick when it hit it.

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