What can I do if I purchased a restaurant and 7 days later discovered Black mold?

I pray I do not have to incur cost from someone who did not take care of his restaurant. The space is leased and has landlords who are willing to do a bit. The prior tenant had a leaky ice machine for sometime. That is where I first discovered the mold. I have never dealt with mold and with the research I am doing, It is terrifying me. I do believe he knew about the mold as I found where he tried to cover it up. Any advise or help would be greatly appreciated. This is in Northern Michigan