Haze chokes Indonesia, Malaysia and Singapore

The capital of Indonesia's Riau province, Pekanbaru, has been cloaked in dense haze for weeks

Smoke from huge forest fires in Indonesian has created a cloud of smog over the country, which has spread over neighbouring Malaysia and Singapore.

The fires, which happen every year, are caused by slash-and-burn clearances on the islands of Sumatra and Borneo.

Paper and palm oil companies have been widely blamed for the practice.

Indonesia, which has repeatedly promised to stop the illegal fires, has sent hundreds of military personnel to try to put them out.

It has declared a state of emergency in Riau province, where the haze has been building for several weeks and pollution levels are hazardous to health.

In Malaysia, schools have been closed in the capital, Kuala Lumpur, and several other areas, while Singaporeans are being advised to avoid strenuous activity outdoors.

Many people have left Pekanbaru but others have struggled on through the haze

Indonesia has sent around 1,000 troops to fight fires in southern Sumatra

It has promised, and failed, to end the seasonal fires many times in the past

Pulp, paper and palm oil companies that own large forest concessions in southern Sumatra are often blamed for illegal fires

In the Malaysian capital, Kuala Lumpur, there was rooftop swimming under hazy skies

The Malaysian prime minister also had to endure the haze, which enveloped his office building

Most - but not all - Singaporeans stayed indoors, as their Environment Agency raised the pollution index to its highest level in a year

Singapore's National Stadium was barely visible from the BBC's studios

The haze could obscure all but track-side views at this weekend's Singapore Grand Prix - officials say they are monitoring the situation.