Kuala Lumpur - Thousands of schools across Malaysia and Indonesia were closed on Thursday as toxic fog caused by forest fires slashed air quality.
Malaysian authorities have ordered the closure of some 2,5,000 schools, including about 300 in the smog-scarred capital Kuala Lumpur, due to growing health concerns caused by toxic fog caused by fires on the Indonesian islands of Sumatra and Borneo.
Hundreds of schools in the severely hit Riau province in Sumatra will be closed on Thursday, with 800 schools closed in just one province, while about 1,300 schools in Kalimantan province in central Borneo have been closed, Indonesia said.
The closures have affected at least 1.7 million students in Malaysia.
Jakarta is deploying thousands of security forces and fire fighters, which have often started with deliberate and illegal fires designed to prepare forest land for agriculture.
Southeast Asian fires erupt every year, but this year has seen the worst fires since 2015 and heightened global fears of forest fires across the globe as they contribute to global warming.
Thursday's closure marks the first mass closure of schools in Kuala Lumpur, where air quality has fallen to "unhealthy" or "very unhealthy" levels, according to a government index in several places in Malaysia, east of Sumatra, where heavy fog covered the capital
The Malaysian state of Sarawak, which is on Borneo island, is plunged into toxic fog, and diplomatic tension in the region is mounting because of the environmental crisis.