This is bad news in the front of an already crumbling crypto sector in India. The hackers know that they can hit exchanges and come out with billions.
It would be interesting to see if the legal approach would take any effect on the existing pea-brained politicians about their approch to cryptocurrencies and the public outcry that will happen.
Never store coins on exchanges, something that I cant emphasize enough. Unfilled trades will get affected, you cant do anything about those in such cases.
Looks more like an internal job to me as thier multi signature wallet was hacked. They may come up with excuses and create a story around this hack but without internal assistant the hacker could not have done a cyber attack. The legal action can only be taken if the users who were affected by the attack raise an FIR. Till now I do not think an FIR has been raised either by the exchange or those affected users. It is imperative that exchange wallets should always be avoided to store coins. A personal wallet with backup and less access to the internet is always considered good practice.