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A thick haze cloaked parts of Malaysia on Wednesday, including the capital Kuala Lumpur, after smoke from forest and peat fires filled the air.

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The top of the Petronas Towers, one of the world's tallest buildings, was almost invisible from the ground.

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Many people wore masks or pressed handkerchiefs to their faces when outside. Officials said the pollution - the worst since 1998 - was already causing health problems.

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The government bowed to public pressure and released previously secret figures on air quality, saying schools would be closed if the problem got worse.

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Tourists, too, were affected. Famous landmarks almost disappeared in the haze.

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Malaysia says hundreds of forest fires are raging on the Indonesian island of Sumatra, sending pollutants across the Malacca Strait and into Malaysia.

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But the pollution levels are also due to fires closer to home. In recent weeks firemen have been battling against peat fires outside Kuala Lumpur.