Renter with dog. Who is responsible

[Carol ODell]

I’m definitely new with rental property. First the lease is up and I’m considering asking them to move. I allowed them to have 1 dog but through out the year they have added a second dog without my consent. The dog (boxer) attacked the neighbors 4lb dog and it had to be put to sleep. My question I guess is if the boxer bites someone who is held responsible/accountable? I do carry homeowners however they carry no insurance. Thanks for all the input I may receive