help advise please tennents growing Cannabis

Hello im new here and could do with some help and advise
Yesterday evening my rented out property was raided by the boys in blue
They found 2 rooms converted to growing cannabis
The 3 tennents were arrested
Lucky for me one of the officers told me they havent bypassed the electric meter
I want to know how I stand
I was told I cant change the locks
I want them out
There is 2 months left on there tennency agreement
Thanks in advance for any help and advice
Stu