Did Mumbai police get no tip-offs about the migrant crisis?

In one of the most shocking developments, Mumbai's Bandra saw a huge gathering as thousands of migrants wished to reach home amid lockdown. This happened hours after Prime Minister Narendra Modi announced an extension of nationwide lockdown till May 3. But amid all this, one question that arises is that why was Mumbai police unaware of the development? Why did the intelligence agencies have no tip-off about the incident?