Answer:
them
Explanation:
As english is an alive language, this means that people continues to use it, changes can happen over time, and with this changes we would have to have or create an standar and non standard way of talking and expressing our ideas, in this case, the standar way of sayin that sentence would be "Leave the papers here", but Leave them papers is a non standard way of sayin it, because many people use it, but it´s not technically correct.