NEW YORK， Dec. 10 (Xinhua) -- Scientists have for the first time detected radiation from Japan's 2011 Fukushima nuclear disaster on the west coast of the United States， local media reported.
The radioactive matter， in the form of an isotope known as cesium-134， was collected in seawater samples from Tillamook Bay and Gold Beach in the U.S. northwest state of Oregon， according to a report released by New York Post Friday.
The levels are very low and cannot harm people eating fish from the West Coast or swimming in the ocean， Ken Buesseler， a senior scientist at Woods Hole Oceanographic Institution， was quoted as saying by USA Today.
"To put it in context， if you were to swim everyday for six hours a day in those waters for a year， that additional radiation from the addressed cesium from Japan is 1，000 times smaller than one dental x-ray，" said Buesseler.
On March 11， 2011， a massive 9 magnitude earthquake， the strongest quake ever recorded in Japan， created three tsunamis that knocked out the Fukushima-Daiichi plant， causing the worst nuclear crisis since the Chernobyl disaster three decades ago.
Massive amounts of contaminated water were released from the crippled nuclear plant， more radiation was released to the air， and then fell to the sea.
"We don't expect to see health concerns from swimming or fish consumption， but we would like to continue monitoring until (the radiation level) goes back down again，" said Buesseler.
SAN FRANCISCO， Dec. 5 (Xinhua) -- A prosecutor vowed there would be "no stone unturned" to look into the warehouse fire in Oakland， California， that has led to the confirmed death of 36 people as of Monday afternoon.
Alameda County District Attorney Nancy O'Malley， appearing in public for the first time since the deadly fire on Friday night， told a press briefing that investigators would try to find evidence of criminal liability and then decide who would be liable.
Charges to be brought against those liable， O'Malley said， could be homicide or involuntary manslaughter. Declining to go into details and reassuring her determination to seek justice for victims and their families， she said experts would examine debris from the two-story warehouse and extra charges would be possible based on evidence.
Investigators had already interviewed "several people" related to the fire， she added.
At the same briefing， Alameda County Sheriff Gregory Ahern said of the 36 bodies recovered from the scene， including three added to the total on Monday morning， 33 had been "tentatively identified." Among them， three were foreign nationals from Finland， South Korea and Guatemala respectively， and their families had been notified.
Noting that about 75 percent of the site was cleaned， Ahern said earlier "we can't locate any other deceased victims" and "we are not anticipating any more huge numbers."
However， three days after the disaster took place， nobody knows how many people were inside the building.
The worst fire in the history of Oakland， in northern California， on the U.S. west coast， prompted Mayor Libby Schaafa and other city officials to go into defensive mode in face of criticism that the city ignored complaints from residents about the specific building and similar situations in the city.
Schaafa said priorities for now are to recover victims and help their families.
The warehouse， known as "The Oakland Ghost Ship，" was permitted only for storage purposes. However， the structure in an industrial neighborhood of East Oakland was converted into art studios， a party venue and probably a residence. Oakland Fire Chief Teresa Deloach-Reed said on Saturday there was no sign of fire alarms and no evidence of a sprinkler system.
The fire started at about 11:30 p.m. on Friday and continued into the Saturday morning， trapping people at what appeared to be an underground music event.
Overnight， authorities released names of seven victims that had been positively identified. All of them were in their 20s and 30s and Californians， including 4 Oakland residents and 2 others from nearby cities in northern California. The name of an additional victim， a 17-year-old minor， was withheld.
An internal wall of the building was found unstable on Sunday night， forcing firefighters to stop searching for victims for several hours. The operation resumed in the morning， and a big crane was brought in to help with the work.
A series of photos were presented to the press in the afternoon， to show what a firefighter called "heat residues" possibly indicative of the origin of the fire， the extensive damage to the structure and a huge amount of debris inside the warehouse.
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