Preparations are underway in India for the upcoming general election, with the first phase set to take place on April 19th. Nearly one billion people are eligible to cast their ballot in what is the world's largest democratic vote.

An indelible ink producer in southern India is operating at full capacity. Election officials will use the ink to mark people when they cast their ballots to prevent repeat voting. The ink leaves a stain that lasts two to three weeks.

The firm says it has already produced more than 2.5 million bottles and is making another 80,000 a day to meet demand.

The election will be held in seven phases through June 1st. Officials are setting up over a million polling stations across the country for the 6-week-long marathon vote.

The result will be announced on June 4th.