At least, 10 electronic voting machines (EVMs) were replaced when discrepancies were detected during their mock trial here before the beginning of the polling.
Rakesh Kumar, Sector Magistrate Bijnor, said: "There were reports that some EVMs were displaying 'lotus' symbol after pressing the button against 'elephant' symbol at some polling booths."
"The elections are being held peacefully here. There were some issues during mock polling. So we changed the entire set of EVMs," Kumar said.
In Bijnor, there is a three-cornered fight among Bahujan Samaj Party (BSP) candidate Malook Nagar, Congress' Nasimuddin Siddiqui and BJP's sitting MP Kunwar Bharatendra Singh.
The voting for the first phase of general elections is underway for eight out of 80 Lok Sabha seats in Uttar Pradesh.