TOKYO, March 13 (Kyodo) — A third-party panel concluded Wednesday that Tokyo Electric Power Co. did not intentionally provide erroneous information to a Diet-appointed committee tasked to investigate the 2011 accident at the utility's Fukushima Daiichi nuclear power plant.

The panel was set up in February after media revealed that a TEPCO official told an investigation committee member in February last year that the fourth floor of the building housing the crippled No. 1 reactor was in "complete darkness," -- which was not true -- leading the committee to give up an on-site inspection.

The committee had placed importance on studying the No. 1 unit as part of efforts to shed light on whether any important reactor equipment had sustained damage due to the March 2011 earthquake, before the ensuing tsunami ravaged the plant.

According to a report compiled by the third-party panel consisting of three lawyers, the TEPCO official provided the incorrect explanation because he "misunderstood" the situation inside the reactor building.

The report also denied that the official was ordered by his superiors to provide such information.

The No. 1 reactor suffered a core meltdown and the building housing the reactor was damaged by a hydrogen explosion in the early days of the nuclear crisis.

TEPCO had installed a cover around the building to reduce the release of radioactive substances into the air, but sunlight was able to penetrate the cover and lighting equipment was attached to the cover at the time TEPCO made the explanation to the investigation committee.

In receiving the report from the panel, TEPCO President Naomi Hirose apologized over the incident and vowed to take measures to prevent a recurrence.