Frank Lapidus shows up in the jungle with a first aid kit for Keamy's team, but comes across Miles, Sawyer, Claire and Aaron first. Frank helps them by telling them to hide because Keamy is close. He sees their position with his satellite phone.
The big question is, why didn't the smoke monster kill Keamy and his team? They all seem to be fine except the one guy who we saw dragged into the jungle in "The Shape of Things to Come."