What did they drop?

On my way to school today, I was riding behind to Vietnamese custom officials on 3 Thang 2 street.  They are easy to recognize in their light blue shirts and navy blue slacks.  All of a sudden I saw one of the custom officials drop a bunch of forms forcing me to swerve to the left.

Hmm, they looked like some official forms but I am not sure.

I wonder what they were...