New Species Being Seen In America

I am wondering if maybe the chupacabra etc people have been seeing in the US are maybe animal experiements that have escaped from Laboratories . The US government seems to not take it seriously making me wonder if they have something to cover up . When officials hear about dead animals appearing they arrive and take the animals away and are never heard of again . Why ? What are they hiding . Why do they keep playing it down . Is it just my suspicious mind or how do others feel .