"An error was reported in the EVM machine in the beginning at booth number 57 of Kolaras, but it was rectified and polling began soon after," the official said.
The by-polls were necessitated due to the death of Congress MLAs Mahendra Singh Kalukheda (Mungaoli) and Ram Singh Yadav (Kolaras).
"Polling is going on peacefully at all the polling booths in the two constituencies and no untoward incident was so far reported from anywhere," Madhya Pradesh's deputy chief electoral officer SS Bansal told PTI.
A total of 22 candidates are in fray in Kolaras while 13 are trying their luck in Mungaoli.
The total number of voters in the two constituencies are 2,44,457 (Kolaras) and 1,91,009 (Mungaoli).
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