Consider the following statements regarding Vinayak Damodar Savarkar:

1. He founded a secret revolutionary organization named 'Mitra Mela' in 1899, which later became famous as 'Abhinav Bharat' in 1904.
2. He wrote the famous book 'The Indian War of Independence 1857', in which he described the 1857 revolt as India's first war of independence.
3. After his release from prison, he propounded the concept of 'Hindutva' and served as the President of the 'Hindu Mahasabha' in 1940.
4. He established the 'Patit Pavan Mandir' with the aim of ending caste discrimination and ensuring temple entry for all castes.

Which of the above statements are correct?