Hi - my name is XXXXX XXXXX I'm a Real Estate
litigation attorney. Thanks for your question, but I'm certainly sorry for you and these tenants having to go through this terrible event.
A.R.S. § 33-1366 discusses damage or destruction by fires, floods and other circumstances that renders the property "substantially impaired." The statute provides two remedy options. The first is to totally vacate and terminate the lease, having no further liability for rent. The other is to vacate only the part of the premises that is damaged, paying a reduced rent.
Thus, the law allows the tenants out of the lease and they can walk away if they choose. If they want to relocate, then you can do so and institute a new lease.
As for their contents, you have no legal responsibility and if they don't have any insurance, it would be up to them to replace their property.
As for the tenants that have no electricity, the tenants can relocate to a hotel until service is reinstated, and just take the cost of the hotel out of the rent, or some other arrangement you can agree to.
From a moral perspective, you certainly want to help the tenants through this tough time, and you can offer any relief you wish - - but you're not obligated to do anything other than what is outlined in this statute.