Indian customers experience the Mi 5, Xiaomi's latest flagship devices on March 31, 2016. [Photo provided to chinadaily.com.cn]

Chinese tech firm Xiaomi's founder and CEO Lei Jun revealed in an open letter today that the company has sold one million smartphones in the first 18 days of this month in India.

The first 50,0000 were sold between Oct 1 and Oct 3 during the country's festive season, according to a report dated Oct 5 on tech-blog website Mashable Asia.

Xiaomi sold about 2.3 million smartphones in India during the first two quarters combined this year, according to the report.

Li Lei, a Xiaomi employee shared on his WeChat that it took five months for China's once top smartphone vendor to sell its first one million units in India when it first tapped the new territory beyond its home market.

Lei Jun expressed special thanks in his bilingual open letter to FlipKart, Amazon and Snapdeal, their channel partners in India through which he would like to repeat Xiaomi's overwhelming success in China. The company set a Guinness record of sales of 2.11 million smartphones in 12 hours on April 8, 2015.

Lei has revealed that Xiaomi aimed to achieve the largest market share in India within three to five years but has not disclosed any sales target in the country.

Market research firm IDC's data released on Sept 2 shows that in the second quarter of this year Samsung led with a 28.5 percent market share in the top 30 cities of India, followed by Micromax with 11.9 percent and Xiaomi with 8.1 percent.

It has ascended to 8.4 percent in September, Lei highlighted in his open letter to all Xiaomi friends, also citing IDC data.

However, in the whole Indian market, which saw a total shipment of 275 million units in the second quarter, Xiaomi had not broken into the top five as Samsung took the largest share with 25.1 percent, followed by Micromax with 12.9 percent and Lenovo Group with 7.7 percent, according to IDC.

In April this year, Xiaomi invested $25 million in India's Hungama Digital Media Entertainment, which boasts more than 8,000 movies in Hindi and other Indian regional languages on its platform and over 65 million monthly active users of its music, videos and movies.