Following are main developments after a massive earthquake and tsunami devastated northeast Japan and crippled a nuclear power station, raising the risk of uncontrolled radiation.

• Nuclear plant still emitting radiation but source unclear, says IAEA. The UN atomic watchdog says Japan has not given some information relating to one reactor.

• The U.S. becomes the first country to block produce from Japan's radiation zone, saying it will halt milk, fruit and vegetable imports from areas of Japan near the crippled Fukushima nuclear plant.

• Japanese Prime Minister Naoto Kan says people should refrain from consuming leafy vegetables from Fukushima prefecture and tells the governor of Ibaraki prefecture to hold off on shipments of raw milk and parsley due to the nuclear crisis.

• Japan's health ministry says it has detected above-safety level radiation in 11 types of vegetables from the Fukushima area where the nuclear plants are located.

• NHK broadcaster says radiation has been found in a Tokyo city water purifier and water from the affected purifier should not be given to infants. Purifiers affected by radiation are in Tokyo city proper and five suburban districts.

• Workers struggling to cool reactors at the stricken nuclear plant are unable to continue work at its No. 2 reactor because of high radiation levels, Japan's nuclear safety agency says.

• Two workers at the troubled plant are injured while trying to restore power to its No. 1 reactor, Kyodo news agency says.

• Japan says there is no need to extend a 20-km evacuation zone around the tsunami-damaged nuclear plant, despite elevated radiation readings outside the area.

• Core of reactor No. 1 was a worry earlier with temperature touching 380-390°C, plant operator says. Reactor built to run at a temperature of 302°C.

• Engineers have re-established power cables to all six reactors and have started a pump at one of them to cool overheating fuel rods. Lighting had been restored at one of the control rooms, local media said.

• The World Health Organization said on Tuesday the detection of radiation in food is a more serious problem than first expected, and food contamination is not a localized problem. It says, however, there is no evidence of contaminated food from Fukushima reaching other countries.

• Plant operator TEPCO says a small trace of radiation had been found in the Pacific nearby, but officials stressed the levels were minute and posed no immediate danger.

• Miniscule numbers of radioactive particles believed to have come from the crippled nuclear power plant have been detected as far away as Iceland, diplomatic sources say. But the tiny traces were far too low to cause any harm.

• China and South Korea say they will toughen radioactivity tests on imports of Japanese food.

• Official death toll from earthquake and tsunami exceeds 9,000, Kyodo news agency reports national police as saying.

• The government estimates the total damage from the quake at 16-25 trillion yen ($197-308 billion). The estimate includes damage to roads, homes, factories and other infrastructure, but excludes lost economic activity from power outages and costs arising from damage to the Fukushima plant, as well as the swings in financial markets.

• TEPCO, the crippled plant's operator, may eventually require more than one trillion yen in financing to help it overcome the disaster, Jiji news says.