The fight to regain control of the damaged Fukushima Daiichi nuclear plant is a heroic one, but far from elegant.

Workers bored holes in the roofs of two reactor buildings to keep them from exploding. They set up a firetruck with a giant water cannon that fired for 13 straight hours through the blown-out side of another building, hoping to raise the level in a pond holding spent nuclear fuel rods. And the workers continued to lay cables and navigate through damaged electrical switches in an effort to restore power to the six-reactor complex.

Japanese authorities claimed progress, or at least the next best thing — no sign of things getting worse.

“We have been able to prevent the situation from worsening,” Chief Cabinet Secretary Yukio Edano said Saturday. “I believe we are reaching a big turning point.”

Edano’s words, however, came amid the relentlessly grim statistics of the nation’s tragedy: 7,348 confirmed dead, 2,603 injured, 10,947 reportedly missing, 362,580 evacuated and living in shelters, according to government agencies.

The mood in Japan remained one of nervous anticipation of what new threat might arise. A 6.1-magnitude aftershock struck in Ibaraki prefecture, rattling buildings in Tokyo.

The weekend also brought a new, if inevitable, report of radiation contamination in the nation’s food supply. It was found in milk 20 miles from the nuclear plant and even farther away, about 60 miles, in spinach collected on half a dozen farms, according to the Associated Press. Traces of radioactive iodine also were discovered in tap water in Tokyo and other cities.

Officials urged calm, saying the detected amounts of radiation are not harmful. Edano said that further tests would be conducted and that the government would ban the sale of any contaminated food products. “Human beings are exposed to a certain level of radiation in daily life. Please react calmly,” Prime Minister Naoto Kan’s office wrote on its Twitter account after the Saturday news conference.

But milk is a particularly sensitive issue when radiation fears arise. After the Chernobyl nuclear accident in Ukraine in 1986, cows fed on contaminated grass and produced milk that was blamed for 6,000 thyroid cancer cases, mostly among people who were children at the time of the accident.

The escalating crisis prompted Kan, of the ruling Democratic Party of Japan, to propose the creation of a coalition government with the Liberal Democratic Party, the largest opposition group. But on Saturday, LDP leader Sadakazu Tanigaki rejected Kan’s offer that he become deputy prime minister, citing policy differences. Kan had reportedly hoped the move would make it easier to pass legislation aimed at helping the disaster response.

At the Fukushima Daiichi plant, a bolstered force of technicians and engineers are scrambling to keep water levels from dropping in reactors and storage ponds. There are six reactors on site, and all six have problems.

Units 1, 2 and 3 were in operation when the earthquake hit and apparently have sustained partial meltdowns of the cores that hold the nuclear fuel rods. The buildings housing reactors 1, 3 and 4 have been severely damaged in explosions. The water level is dangerously low in the spent-fuel pools for units 3 and 4, and the temperature is too high in the pools in units 5 and 6.

Water is used as a radiation-shielding measure and for cooling the nuclear fuel, which, though not undergoing fission, is still throwing off heat through the decay of particles. Without electricity to power the cooling systems, water has been heating up and evaporating, leaving fuel rods exposed inside the reactors themselves and in the storage ponds.

Because the radiation levels have been so high, the crews resorted partially to automation. Operating in the dark, and braving the invisible atomic fog, the workers set up a firetruck with a 70-foot-tall water cannon that could automatically spray three tons of seawater a minute through the walls of the building containing the unit 3 reactor.

The crews did not have to man the truck other than to periodically refuel it. The reactor itself is enclosed, but there is an open-air pool used for storing spent fuel rods. Earlier attempts to add water by dumping it from helicopters proved ineffective.

Tokyo Electric Power Co. (Tepco) announced a positive step in the unit 5 reactor’s spent fuel pool, saying it had restored electrical power on that unit and restarted a heat removal pump early Saturday. The temperature is now dropping. The company also took a step to ward off the potentially explosive buildup of hydrogen gas in the buildings housing units 5 and 6, knocking holes in the roofs.

On Sunday, emergency workers initially feared a setback in the No. 3 reactor as dangerous pressure built up inside in the wake of the seawater being pumped into the facility a day earlier. Officials initially said they would be forced to vent the steam to relieve the pressure buildup, which could potentially further damage the facility’s reinforced nuclear containment chamber.

Pressure in the reactors normally is released through a suppression pool at the bottom of the plant, but that has not worked since power was cut during the tsunami. If released into the air, the steam likely would carry radioactive material into the atmosphere, officials acknowledged, and that could potentially endangering people and contaminating crops in the region.

But by Sunday afternoon, Endo proclaimed at a news conference that experts concluded that they would not need to immediately vent the steam and instead would keep watch over pressure levels.

The plant has been largely blacked out since the tsunami generated by the March 11 earthquake obliterated the coastal installation, knocking out the diesel generators that were supposed to be a backup to the normal electrical grid. Tepco is trying to restore power incrementally to nuclear reactors. The company has said it hopes to have power in the unit 1 and 2 reactors Sunday.

Even if power does come back, there is no guarantee that the cooling systems will operate correctly.

The fears of radiation have incited many foreigners to leave Japan. On Saturday the U.S. military flew more than 200 military family members back to the United States from Yokota Air Base.

One story of human endurance that prompted news bulletins around the world Friday turned out to be untrue. A man, news agencies reported, had been rescued from the rubble of his home in Miyagi prefecture, eight days after the earthquake. But, in fact, he had spent a week at an evacuation center and had merely returned home hoping to clean up, his family said.

Achenbach reported from Washington. Special correspondents Akiko Yamamoto and Kyoko Tanaka contributed to this report.