Tenant was evacuated for 3 days, how to handle?

[Brian Reynolds]

My rental house is located in Santa Clarita CA, where the big forest fire "Sand Fire" just went crazy last week. My property was close to the burn area, but no damage. The area was under mandatory evacuation for 3 days, and my tenants left, wisely. I believe they stayed with family, don't think they paid for hotel. 

Should I give a rent credit for those 3 days? Extend the time to pay rent? Or business as usual? My lease doesn't handle this exact situation, just if the property is beyond livable condition and they have to end their lease.