Bank of America denying $5,000 in fraud claims.

I was in cancún and a gang of three people stole my wallet and phone.

I now have three charges: 2 on my credit card and one on my debit card all totaling around $5,000.

I reported fraud to bank of america, and they denied my claim stating I authorized the charges, but I did not.

I called backed today and re-opened the claim.

What are your suggestions on what I should do? Would filing a police report help?

Im based in the USA.