Who was Rajya Sabha MP, former SP leader Amar Singh?

Rajya Sabha member, former Samajwadi Party leader Amar Singh died at the age of 64 in Singapore today. He passed away in a Singapore hospital where he was undergoing treatment for kidney ailments. From Vice-President M. Venkaiah Naidu to Madhya Pradesh Chief Minister Shivraj Singh Chauhan condolences poured in as the news broke. Defence Minister Rajnath Singh said Singh was friendly with all political parties. He remembered him as "humorous and always energetic".