Two persons were arrested on Wednesday for allegedly keeping about 10,000 voter cards and over a lakh counterfoils at a flat in Bengaluru's Rajarajeshwari Nagar assembly segment, a senior police officer said.

"Two persons have been arrested, one for committing the electoral offence of keeping several voter cards in one place and another for breaking into the apartment where the voter cards and counterfoils were kept, without informing the Election Commission authorities," Additional Commissioner of Police Bijay Kumar Singh told IANS here.

State Chief Electoral Officer (CEO) Sanjiv Kumar told reporters here on Wednesday that a total of 9,896 voter cards and over a lakh counterfoils resembling acknowledgement slips were seized so far from a flat in the Assembly constituency, ahead of the May 12 assembly election.

Police and Election Commission officials, however, did not disclose the details of the people arrested.

"Preliminary investigation shows that the voter cards are genuine, but the counterfoils are yet to be verified," Kumar said.

An FIR was registered on the incident, he added.

Along with the voter cards and counterfoils, the poll panel officials have also seized survey formats with names of the voters, mobile numbers, caste, Aadhaar number, below poverty line (BPL) card details, and photographs of houses.

"All the materials have been seized and investigation is going on under the supervision of the EC. The entire material indicate a planned work over a period of time to survey and locate the vulnerable electors and induce them through middlemen," Kumar said.

The constituency has a total of 4,71,459 voters, with an elector to population ratio of 75.43 per cent, which is higher than the average across the total 28 constituencies in Bengaluru.

"The Rarajeshwari Nagar constituency had 44,857 voters added to the electoral rolls this year, a 10.3 per cent increase in the number of voters added, as against the state average of 6.04 per cent," Kumar added.

A Deputy Election Commissioner is to soon visit the state to take the stock of the situation.

The ruling Congress blamed the opposition Bharatiya Janata Party (BJP) after the incident, calling it a conspiracy by the party leaders in an apartment that allegedly belonged to a former BJP corporator Manjula Nanjamari.

"In a flat owned by a former BJP corporator, and in a flat rented out to a BJP corporator candidate, how did 10,000 voter IDs come into being? Facing imminent defeat, this is a conspiracy hatched by the BJP leaders," Congress spokesman Randeep Singh Surjewala told reporters here.

The BJP urged the EC to countermand the election in the constituency, calling the incident an attempt by the ruling Congress to allegedly rig the election.

"The BJP demands countermanding of elections in Rajarajeshwari Nagar in light of latest revelations of tens of thousands of fake voter IDs and empty packets of hard currency. This is Congress conspiracy to rig election in the face of their imminent defeat," said Union Minister and the party's in-charge for state polls Prakash Javadekar.