Media playback is unsupported on your device Media caption The BBC's Mariko Oi in Tokyo: ''It was a disaster... made in Japan''

The crisis at the Fukushima nuclear plant was "a profoundly man-made disaster", a Japanese parliamentary panel has said in a report.

The disaster "could and should have been foreseen and prevented" and its effects "mitigated by a more effective human response", it said.

The report catalogued serious deficiencies in both the government and plant operator Tepco's response.

It also blamed cultural conventions and a reluctance to question authority.

Analysis While the report is highly critical of all the key parties, it digs even deeper. The panel called the disaster "Made in Japan", because the mindset that allowed the accident to happen can be found across the country. It flagged up the bureaucracy's role in both promoting and regulating the nuclear industry, and also cultural factors such as a traditional reluctance to question authority. The report was expected to use strong language, but not many thought it would be this harsh. The panel also found that there was a possibility that the plant was damaged by the earthquake, contradicting the official position that only the tsunami contributed to the disaster. It could put further pressure on the government, which recently authorised the restart of two nuclear reactors in western Japan. They were declared safe in April but the plant also sits on top of a fault line.

The six-reactor Fukushima Daiichi nuclear plant was badly damaged after the 11 March 2011 earthquake and tsunami knocked out cooling systems to reactors, leading to meltdowns and the release of radioactivity.

Tens of thousands of residents were evacuated from an exclusion zone around the plant as workers battled to bring reactors under control. Tepco declared the reactors stable in December 2011.

Members of the Fukushima Nuclear Accident Independent Investigation Commission were appointed to examine the handling of the crisis and make recommendations.

The investigation included 900 hours of hearings and interviews with more than 1,000 people.

'Insular attitude'

In the panel's final report, its chairman said a multitude of errors and wilful negligence had left the plant unprepared for the earthquake and tsunami.

"Although triggered by these cataclysmic events, the subsequent accident at the Fukushima Daiichi Nuclear Power Plant cannot be regarded as a natural disaster," it said.

KEY FINDINGS Collusion and lack of governance by government, regulators and Tepco

by government, regulators and Tepco Insufficient knowledge and training within Tepco

within Tepco Lack of preparation on part of government, regulators, Tepco, and prime minister's office to allow adequate response to accident of this scope, including mounting effective evacuation

on part of government, regulators, Tepco, and prime minister's office to allow adequate response to accident of this scope, Laws and regulations based on stopgap measures in response to previous accidents - need comprehensive review Fukushima report: Key points

"It was a profoundly man-made disaster - that could and should have been foreseen and prevented."

After six months of investigation, the panel concluded that the disaster "was the result of collusion between the government, the regulators and Tepco" founded in the failure of regulatory systems.

It said that the situation at the plant worsened in the aftermath of the earthquake because government agencies "did not function correctly", with key roles left ambiguous.

It also highlighted communication failures between Tepco and the office of then Prime Minister Naoto Kan, whose visit to the site in the immediate aftermath of the earthquake "diverted" staff.

The report said regulators should "go through an essential transformation process" to ensure nuclear safety in Japan.

"Japan's regulators need to shed the insular attitude of ignoring international safety standards and transform themselves into a globally trusted entity," it said.

Fukushima disaster Reactor cooling systems damaged after 11 March earthquake and tsunami

Explosions occurred on 12-15 March at four reactors after gas build-up

Tepco engineers injected seawater into reactors for cooling

Contaminated waste-water leaked on several occasions

Meltdowns later confirmed at three reactors

Tepco declared 'cold shutdown' - meaning reactors were stable - in December 2011 Fukushima versus Chernobyl? Loss and recovery in numbers

The report made several recommendations including:

Permanent parliamentary monitoring of the nuclear regulatory body

Reforming the crisis management system, with more government responsibility for public welfare

Reforming nuclear energy laws to meet global safety standards

Monitoring nuclear operators and developing a system for independent investigative bodies

All of Japan's nuclear plants were shut down in the wake of the disaster. But on Sunday the first reactor was restarted in the town of Ohi in Fukui prefecture.

The restart sparked large protests in Tokyo but Prime Minister Yoshihiko Noda urged support for the move, saying a return to nuclear power was essential for the economy.

The government is continuing to assess whether other nuclear plants are safe to be restarted.