Top Japanese and Chinese police officials agreed Monday to spur investigations into toxic dumpling cases by offering evidence the two countries have collected to each other, Japanese officials said. The accord was reached when top officials from Japan's National Police Agency held talks with their Chinese counterparts in Beijing on Monday night. They also agreed on greater collaboration to settle the food poisoning cases involving Chinese-made dumplings, which caused 10 people in two Japanese prefectures to fall ill, the officials said.