Days after the last vote was cast on May 19 for Lok Sabha elections, a high-level Opposition delegation met the Election Commission on Tuesday expressing concerns over alleged tampering with the Electronic Voting Machines (EVMs) even as protests were held in some states.The EC, however, dismissed all reports of EVMs being manipulated saying that all EVMs and voter verified paper audit trail machines (VVPAT) were sealed properly and stored in guarded strong rooms.Nearly four million EVMs were used in the Lok Sabha election this year as millions of voters cast their ballot during the five-week long process.Here’s a look at what happens to the EVMs after the last vote is cast:* The EVMs are sealed immediately after polling for the day ends and polling agents put their signatures on the seal. * Guarded by central paramilitary forces, EVMs are then taken to strongrooms and kept there until the day of counting of votes. This year, vehicles carrying reserved EVMs and VVPATs during the seven-phased Lok Sabha polls were mandatorily equipped with global positioning system (GPS) to track their movement.* These strongrooms with power backup and CCTV cameras are guarded round-the-clock. The polling agents can go up to the strongroom during the transportation of EVMs.* The candidates or their representatives can also put their own seals on the strongroom doors. The poll body also allows representatives to camp in front of the strongrooms.* The EVMs are taken from the strongrooms to the counting centres again under heavy security on the scheduled day of counting, which is on Thursday this year. Unique IDs of the seals and control units of the EVMs are shown to candidates’ representatives before the counting process starts.* After the counting is concluded, the EVMs are again kept in the strongrooms for almost 45 days to settle the issues related to the machines and votes if there are any.