BEIJING - Beijing will use artificial rainmaking to clear the air after a choking dust storm coated China's capital and beyond with yellow grit, prompting a health warning to keep children indoors, state media said Tuesday. The huge storm blew dust far beyond China's borders, blanketing South Korea and reaching Tokyo. The storm, reportedly the worst in at least five years, hit Beijing overnight Sunday, turning the sky yellow and forcing residents to dust off and hose down cars and buildings. Hospitals reported a jump in cases of breathing problems, state television said. The government was preparing to seed clouds to make rain to clear the air, state TV said, citing the Central Meteorological Bureau. It did not elaborate, and the bureau refused to release more information. Storms carrying chalky dust from the north China plain hit Beijing every spring, but newspapers said this week's was the heaviest since at least 2001. The Beijing Daily Messenger said 300,000 tons of sand and dust were dumped on the city Monday. That was "definitely one of the most serious pollution days in Beijing," weather forecaster Yang Keming said, according to the China Daily newspaper. "Small children had better stay at home during such days." The dust reached Tokyo on Tuesday, the first time that has happened in six years, said Naoko Takashina of Japan's Meteorological Agency. Dust from China was found in more than 50 locations throughout the country, she said. The Japanese agency warned of reduced visibility but did not say any health dangers were expected. In South Korea, a light layer of dust blanketed the country, but no ill effects were reported. Rain was forecast overnight Tuesday, and the weather bureau said it should clear the air. The dust storms are expected to last through at least Wednesday in Beijing, neighboring Tianjin and a swath of north China stretching from Jilin province in the northeast through Inner Mongolia to Xinjiang in the desert northwest, the China Daily and other media said. That region is home to hundreds of millions of people. More storms were expected later in the week in Xinjiang and other parts of the northwest, according to news reports. China's government has been replanting "green belts" of trees throughout the north in an effort to trap the dust after decades when the storms worsened amid heavy tree-cutting. Last week, the western Xinjiang region was hit by its worst sandstorm in decades, which killed one person and left thousands stranded after sand covered railways and high winds smashed train and car windows.