Even in the early days of the disaster at the Fukushima Daiichi Nuclear Power Plant in March of last year, as the reactors spiraled out of control, the terse statements issued by the operator felt like an exercise in denial. Radiation readings were “higher than the ordinary level” (about 100 times higher), and a “loud noise and white smoke” had hit the No. 4 reactor (a possible hydrogen explosion).

Now, footage released by the operator from the crisis’s early days — the second set of recorded teleconferences between the command center of the tsunami-hit plant and the company’s headquarters in Tokyo — demonstrates just how little those announcements reflected the chaos and uncertainty on the ground. The gap between the initial assurances given by company and government officials, and the ultimate scale of the nuclear disaster, has helped fuel a crippling public mistrust of government.

The 300 hours of grainy video made public by the Tokyo Electric Power Company on Monday pick up where a previous batch of videos left off, on March 15, five days after the tsunami knocked out the plant’s power. By then, the plant had been rocked by two explosions and the cores of three reactors had melted down, prompting Masao Yoshida, the plant’s unflappable chief, to warn of “acute danger.”

In the early hours of March 15, Mr. Yoshida raised a new concern, this time about flames sighted deep within the building housing the No. 4 reactor, which was shut down at the time of the disaster. But the reactor building housed almost 1,500 highly radioactive spent fuel assemblies in a pool of water, and it was the second fire spotted there in less than 24 hours.

“We would go put out the flames if we could, but we don’t have the tools. We have nothing,” Mr. Yoshida pleaded with headquarters. He inquired whether there was any truth in speculation that the United States Army – which had a presence in Japan – might send a helicopter to help douse the flames with water.

With the plant’s phone lines down, he enlisted the help of personnel at a neighboring nuclear power plant in alerting the local fire brigade, but its calls went unanswered.

Tokyo headquarters soon suggested the company would have to issue a statement: TV networks with cameras trained on the plant could broadcast fire or smoke, leading to panic.

After some tweaking, Tokyo Electric issued a statement saying that a fire had been spotted at the No. 4 reactor building, and that the site personnel were attempting to put out the blaze.

“Calling the fire department counts as attempting to put out the blaze, right?” an official at headquarters said wanly.

The plant personnel were just as evasive when they finally got through to local firefighters, choosing to say nothing about high radiation readings at the plant.

“There’s no use in us telling the fire department. That’s a conversation that needs to happen at higher levels,” an official at headquarters said.

That lack of disclosure backfired, however, when the fire brigade, learning of high radiation levels at the plant’s gates, initially refused to venture in, and even pulled some men back.

The footage also shows that an operation to drop water from military helicopters onto another reactor at the site – hailed at the time by Tepco officials as a success – was received by plant workers with far less enthusiasm.

There was initially tangible excitement in the plant’s control room as workers huddled to watch live TV footage of the helicopters approach one of the reactors. “There it goes” and “Go! Go!” officials can be heard shouting.

But much of the water appeared to miss the reactor, dissipating in a mist of white. “Uhh…,” a chorus of disappointed voices cried out.

“That was just a quick misting,” said an abject voice off camera. “It didn’t hit at all.”