By Josh Levs, (CNN) — A “rat-like animal” just might be the reason for power outages at a critical Japanese nuclear facility this week.

The operator of the Fukushima Daiichi plant suspects such a critter of causing a short circuit in a switchboard that led to a power outage, Japan’s Kyodo news agency reported Wednesday.

Since a devastating earthquake and tsunami in March 2011 that triggered a nuclear disaster at the plant, the switchboard has been on the back of a truck outdoors, the report said.

Tokyo Electric Power Co. has resumed operations at all nine facilities where power outages occurred, including a facility that removes radioactive substances from water used to cool reactors, Kyodo reported.

The temporary power loss did not trigger a known release of radioactive material.