The Bharatiya Janata Party on Saturday mourned the death of Shiv Sena chief  Balasaheb Thackeray, describing him as a lion and one of the most charismatic leaders whose demise has left a "gaping void" in the country's politics.

"It is rare in the 65 years of independent India that I have seen a political leader who has left such a deep and abiding imprint on the country's events as Balasaheb Thackeray. Uncompromising in his patriotism, he possessed remarkable qualities of leadership and abundance of attributes of head and heart," senior leader L K Advani said.

The death of Thackeray has left a "gaping void" in the country's politics which cannot be filled, he added.

Leader of Opposition in Lok Sabha Sushma Swaraj said on Twitter, "I am terribly pained to hear that the Lion is dead."

She later told reporters that very few people have the courage to speak their mind and Balasaheb was one of them. "He was never deterred by any opposition. His persona was as high and firm as the Himalayas. His death is an irreparable loss to the country. His departure has left a void which will never be filled."

In his condolence message, Arun Jaitley, Leader of the Opposition in the Rajya Sabha, said, "He was one of the most charismatic leaders of his generation and uncompromising in his principles."

Gujarat Chief Minister Narendra Modi said on Twitter, "Full of life, Balasaheb Thackeray was an epitome of courage and valour. I am grieved to hear about his demise. May his soul rest in peace."

Speaking to reporters later, Modi said, "His going away is like the passing away of an era. A good cartoonist, a free thinking journalist and one who awakened Maharashtra with his views, he carved a niche for himself in Indian politics.... He kept away from power but built an organization and a movement on his own strength."

BJP President Nitin Gadkari said the death of Thackeray was a personal loss to him.

"What was in his heart was on his lips. He never hesitated to speak his mind. Both the BJP and the Shiv Sena have lost their anchor," he added.