The List

From publisher blurb:

While in Star Port the entire place erupts in gunfire. Machinegun fire rakes the walls around the travelers suddenly and then stops just as suddenly. The attack is over in less than a minute. Lying dead all around the travelers are innocent bystanders and masked gunmen alike. The sound of star port guards rushing in can be heard over the silence and wimpering of the wounded and dying.

One of the dead masked men has a bloody piece of paper clutched in his hand. It appears to be a list of names which have been scratched off. The names of the travelers, themselves, is near the top of this list. Who these masked men are is a mystery that needs solving.