FUKUSHIMA, Japan - (AP) - Japan ordered emergency workers towithdraw from its stricken nuclear power complex Wednesday amid asurge in radiation, temporarily suspending efforts to cooloverheating reactors. Chief Cabinet Secretary Yukio Edano said the workers, who weredousing the reactors with seawater in a frantic effort to stabilizetheir temperatures, had no choice except to withdraw. "The workers cannot carry out even minimal work at the plantnow," Edano said. "Because of the radiation risk we are onstandby." Radiation levels had gone down by later Wednesday, but it wasnot immediately clear if the workers had been allowed back in. The nuclear crisis has triggered international alarm and partlyovershadowed the human tragedy caused by Friday's earthquake andtsunami, which pulverized Japan's northeastern coastline. Officialsbelieve at least 10,000 people were killed, and possibly many more. Since then, authorities have been struggling to avert anenvironmental catastrophe at the coastal Fukushima Dai-ichicomplex, 140 miles north of Tokyo. Wednesday's radiation spike was apparently the result of arelease of pressure that had built up in one of the reactors,officials said, though it was not immediately clear which one.Steam and pressure build up in the reactors as workers try to coolthe fuel rods, leading to controlled pressure releases throughvents - as well as uncontrolled explosions. Officials had originally planned to use helicopters and fire trucksto spray water in a desperate effort to prevent further radiationleaks and to cool down the reactors. "It's not so simple that everything will be resolved by pouringin water. We are trying to avoid creating other problems," Edanosaid. A U.S. nuclear expert said he feared the worst. "It's more of a surrender," said David Lochbaum, a nuclearengineer who now heads the nuclear safety program for the Union ofConcerned Scientists, an activist group. "It's not like you wait10 days and the radiation goes away. In that 10 days things aregoing to get worse." "It's basically a sign that there's nothing left to do butthrow in the towel," Lochbaum said. The government has ordered some 140,000 people in the vicinityto stay indoors. A little radiation was also detected in Tokyo,triggering panic buying of food and water. There are six reactors at the plant. Units 1, 2 and 3, whichwere operating last week, shut down automatically when the quakehit. Since then, all three have been rocked by explosions.Compounding the problems, on Tuesday a fire broke out in Unit 4'sfuel storage pond, an area where used nuclear fuel is kept cool,causing radioactivity to be released into the atmosphere.Links and information for relief effortsJapan races to avert multiple nuclear meltdownsRadiation leaks from Japanese nuclear plant after explosion, fire