Brother transferred our family land without my knowledge, what are my legal options?

Hello, I'm feeling very betrayed right now. I just found out that my brother has transferred our ancestral land in Chennai to his name without informing or taking my consent. This land was jointly owned by us after our father passed away. The property is quite valuable, worth around ₹50 lakhs. I only discovered this because I was planning to propose leasing it out and upon checking the records, it was already in his name. I don't know what steps to take now. Can I contest this transfer legally? What can I do to ensure my rights are protected?