Media playback is unsupported on your device Media caption Video of the inside of Number 2 reactor at the Fukushima Daiichi nuclear plant - video courtesy of Tepco

The first footage from inside one of Japan's tsunami-hit nuclear reactors at Fukushima has been released by the stricken plant's operator.

Tokyo Electric Power Company (Tepco) inserted an endoscope camera in Number 2 reactor to examine the interior.

Thursday's probe aimed to get details such as the true level of cooling water and temperature inside the vessel.

The six-reactor Fukushima Daiichi nuclear plant was badly damaged by the 11 March earthquake and tsunami.

Last month it was announced that the nuclear reactors had finally been stabilised and reached a state of "cold shutdown".

This occurs when the water that cools nuclear fuel rods remains below boiling point, meaning that the fuel cannot reheat.

Radiation distorted footage

The video probe, just 8.5 mm in diameter according to one report, was inserted into the vessel to ascertain reactor conditions, particularly the level of cooling water and the temperature.

Some of the footage was distorted because of the levels of radiation, but officials say no major ruptures caused by the earthquake have been spotted.

"The visual artefacts provoked by the high level of radiation and other leaks inside are a viewing obstacle, but nevertheless the images are of relatively good quality in some areas," Tepco official Junichi Matsumoto is quoted as saying by the Associated Press news agency.

Tepco also said that experts were still trying to identify all the parts that were shown in the video.

The probe failed to find the water surface, which indicates that it sat at lower than expected levels and raised questions about the accuracy of current water monitors.

But the probe confirmed that the temperature inside the reactor was in line with the temperature gauge outside the container.

The information from the probe "will help us keep the reactor stable and solve problems," Ms Matsumoto is quoted by Reuters as saying.

Reports say that Tepco now hopes to use the endoscope to look inside two other stricken reactors but officials say radiation levels would have to decrease before that can happen.

A 20km (12m) exclusion zone remains in place around the plant. The government says it will take decades to dismantle the plant completely.

More than 80,000 people had to leave the area. Radiation levels in some places remain too high for them to return home.