Patna, July 3 (Reporter) With the collapse of three more bridges in Siwan and one in Saran district on Wednesday, a total of ten bridges have collapsed in the last 15 days in Bihar. Officials have said with the onset of the monsoon, and the strong current of the river, the pillars of the bridges sank deeper and weakened, leading to cave-ins. The lack of maintenance has also been described as a causative factor, with Chief Minister Nitish Kumar directing authorities to prepare a maintenance policy of bridges of the Rural Works Department. The state government, taking serious note of such incidents, has also ordered a thorough probe to find out the exact reasons behind the series of bridge collapses.The government has warned that those found guilty would be given stringent punishment. Three bridges collapsed in Siwan while one bridge gave way in Saran district on Wednesday . In Siwan, one bridge each collapsed in Patera, Tweta and Dhamai villages. A portion of the bridge over the Gandaki river in Patera village of Deoria block collapsed in Siwan district. It was constructed in 1982-83 and repair work was in progress, said Deputy Development Commissioner Mukesh Kumar. It appeared that the rise in water level and strong current of Gandaki river could be the reason behind the bridge collapse but exact cause would be known only after an inquiry, he stated. As it is, a bridge had collapsed over Bund river in Khushi Dhangi village in Kishanganj district last Saturday while another bridge in the district broke down in Bansbari village on June 26. In similar incident, a bridge collapsed in the Araria district on June 18. Another small bridge on a canal of the Gandaki river gave way in Siwan district on June 22 while an under-construction bridge caved in in East Champaran district on June 23. A bridge had also collapsed in Madhubani district on June 27. The collapse of ten bridges in last 15 days in Bihar has become a big political issue for the opposition in Bihar. All opposition parties in the state have slammed the Nitish Kumar government for rampant corruption in administration which led to such incidents. Meanwhile, Nitish held a high-level meeting to review the maintenance of all bridges in the state. He directed authorities to prepare the maintenance policy for bridges of the Rural Works Department on the lines of those followed by the State Road Construction Department earlier. Those found guilty of dereliction in discharging their duties, would not be spared, he warned...////...