Thiruvananthapuram: Hundreds of people in Alappuzha and Kollam districts have been moved to relief camps following torrential monsoon rains in Kerala since the past three days, an official said on Sunday. The Southwest monsoon set in over Kerala and Lakshadweep on Wednesday. The continuous rain has led to a considerable drop in temperature -- from over 40 degrees to 31 degrees Celsius, according to an IMD statement issued here on Sunday. Alappuzha and Kollam are worst affected due to the monsoon fury. At Kuttanad, in Alappuzha district, a temporary band that separated the backwaters from around 350 acres of paddy land, gave way. The land was being readied for a new crop. The loss is estimated at over Rs two million. Flood waters have entered more than 200 houses, forcing residents to leave. Most have gone to the homes of relatives or are at the relief camps. State Agriculture minister V.S. Sunilkumar has asked ministry officials to visit the affected areas and prepare a report on the damage to agriculture crop. At Mankada, in Malappuram district, a major tragedy was averted as the roof of three classrooms of a state-run school collapsed following heavy rain. It being a Sunday and a holiday there was no one present. Southwest monsoon normally sets in over Kerala around June 1. It advances northwards, usually in surges, and covers the entire country around July 15.