How land clearing in Indonesia sparked haze
25 June 2013 Last updated at 02:31 BST
Indonesia's president has apologised for the thick clouds of smoke that continue to drift from the fires in Indonesia to other parts of South East Asia.
The smog is blamed on farmers using a "slash and burn" method to clear land for palm oil plantations.
The BBC's Rupert Wingfield-Hayes reports from the Indonesian province of Riau - explaining how the slash and burn method is harmful for the environment.