Jakarta – Forest and ground fires, mainly blamed on land clearing practices, have led to the return of haze over parts of the Indonesian province of Riau in Sumatra island, officials and police said.

The haze, afflicting the region for about two weeks, was thickest around the oil town of Duri, said an official of the province's meteorology office. "The haze has returned for some two weeks and has been quite thick in the past few days," said police Second Sergeant Siringo-ringo in Duri.

"Visibility is only around about 30 meters and many on the streets are already wearing surgical masks," he said. He said the sun was not getting through the thick smoke which he said came from fires in forest and from land clearing in the areas around the town and that houses had their lights on during the day. "It has been like this for at least three days, from dawn to dusk," Siringo-ringo said.

The meteorology official in Pekanbaru, the capital of Riau province, some 45 kilometres south of Duri said that in Pekanbaru itself, haze was thin and did not affect visibility much during the day. "Early in the morning, visibility is around one kilometer but around noon it is usually already around five to six kilometres, so the haze is not yet a problem here," said the official, who only identified himself as Ibnu. Unlike in Duri, Pekanbaru has seen some drizzles that have helped clear the sky.

Another official, Anwar said the haze in Duri was mostly due to traditional land-clearing using fire to prepare for the new crop season. "The government has continued to warn the people about the negative effects of such land-clearing practice, but farmers are continuing with the burning of their fields because there is no enforcement and it is the most affordable way for them to clear their land for new crop," Anwar said.

The government has banned land clearing by fire following the series of widespread forest and ground fires that cast smoke and thick haze over the region and also covered the skies over Singapore and Malaysia for months.