Earlier, the commission had said that it would invite all the national and state recognised parties which had contested the recent assembly polls. Some of these parties had alleged that the EVMs were tampered with.
Now, the poll panel has sent letters to all the seven national parties -- the BJP, the BSP, the Congress, the CPI, the CPI-M, the NCP and the TMC -- and 49 state parties, including the AAP.
The BSP and the AAP were the first to question the reliability of the EVMs. The BSP, along with several other parties, had urged the commission to revert to the paper ballot system saying the faith of the people has eroded in the machines.
As the AIADMK now has two factions recognised by the poll panel, both have been invited for the challenge.
But the commission has kept out smaller registered but unrecognised parties and independent candidates who contested polls in Uttar Pradesh, Uttarakhand, Punjab, Goa and Manipur.
Each party will get four EVMs of their choice from the five states and four hours to hack. Each team can have a maximum of three persons. But foreign experts have been barred from participating.
The challenge begins on June 3.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)