Indonesia's environment minister said on Friday some forest fires in its territory had started on land used by subsidiaries of Malaysian companies, as the neighbors traded blame for blazes that have spread haze across the region. Malaysia has said smoke from fires on Indonesia's Sumatra and Borneo islands over the past month has drifted over the border, forcing it to close schools and issue public health alerts. Indonesia has dismissed those accusations saying fires have broken out in other countries - and Environment Minister Siti Nurbaya Bakar told Reuters some of the fires in Indonesia had been spotted in palm oil plantations owned by at least four subsidiaries of Malaysian companies. The plantations had been sealed off after the fires were spotted, she said. Two of the Malaysian parent companies said their subsidiary's plantations had not been sealed off as a result of any fires and they were on high alert for blazes. A third company confirmed a fire in its plantation, while the fourth did not respond to requests for comment. Southeast Asia has suffered for years from annual bouts of smoke caused by slash-and-burn clearance of forests for farms and palm oil plantations, raising worries about public health and the impact on tourism. -Reuters