Russian Aid to Ukraine: Trojan Horse or Goodwill Offering?

Russia dispatched a massive convoy of trucks towards Ukraine recently.  According to Moscow, these trucks are jam-packed with humanitarian aid and supplies.  Western countries have warned against using such tactics as a cover for invasion, and Ukraine is concerned about letting these trucks cross the border.

There is a lot of distrust brewing on both sides and the concern over this action, particularly with Russian military forces on the border, is understandable.  What if Russia is sending aid, just as they said?

Will this spark another incident?  Are Russian motives clean?