From Zelda Dungeon Wiki
A Link to the PastLink enters the Lost Woods, Thieves will charge at Link as soon as they spot him. Their goal is to ram into Link, causing him to drop Rupees, Arrows, and Bombs. The Thief will then proceed to collect the items Link has scattered about. These thieves will only steal items from Link and cannot cause him physical harm. Likewise, Link is unable to defeat the thieves and can only just avoid them.
Four Swords Adventures
Thieves will steal Force Gems from Link when they charge into him.
While in Kakariko Village, 10 thieves will need to be captured and tossed into a fenced area, allowing access to the northern portion of the Village.