Revealing mistake: When the survivors are walking in the rain and find the cabin, they are sopping wet, only a few minutes later they are perfectly dry. You can not dry out that quickly in the tropics.
Factual error: When the soldiers are bombing the camp site they only use grenade launchers and the explosions are huge, far too large for one grenade.
Factual error: When the bomb explodes, the entire house is blown up and a police car near it flies into the air, but Sam, the mayor's daughter and the other policemen are not really affected by that. They are only at the other side of the street.
Visible crew/equipment: When the house blows up you can see the air cannons that provide the effect.
Factual error: The wind and the rain come and go throughout the movie. In the middle of a hurricane? I don't think so.
Factual error: Towards the end of the film when the old man shoots the soldier point blank with a machine gun, the bullet should go through the soldier and the people in front of him.
Factual error: The 2 characters near the end are struck by lightening next to a big tree, the lightning would strike the tree and not them.
Continuity mistake: At the beginning of the movie, Sam tries to shut down the bomb. The timer reads 24 seconds. When he discover that he can't, something like 1 second later, the timer reads 19 seconds.