A disaster occurs in a queue when a negative arrival causes all the wo
rk (and therefore customers) to leave the system instantaneously. Rece
nt papers have addressed several issues pertaining to queueing network
s with negative arrivals under the i.i.d. exponential service times as
sumption. Here we relax this assumption and derive a Pollaczek-Khintch
ine-like formula for M/G/1 queues with disasters by making use of the
preemptive LIFO discipline. As a byproduct, the stationary distributio
n of the remaining service time process is obtained for queues operati
ng under this discipline. Finally, as an application, we obtain the La
place transform of the stationary remaining service time of the custom
er in service for unstable preemptive LIFO M/G/1 queues.