Who pays for tenants accomodation in case of emergency?

[Lena S.]

  Two weeks ago, we've got a call from one of our tenants about gas leaking outside our property. We immediately called the service, they came and fixed the problem, and since there was not signs of  gas leaking inside the building all tenants could stay in their apartments. Above situation actually make me wonder what if all tenants has to be evacuated from the building and need to go to sleep somewhere else, Are landlords or tenants themselves responsible to find and pay for their temporary place?