Chinese scientists landed on a disputed South China Sea reef over the weekend in the latest assertion of Beijing’s sovereignty claims. The uninhabited sandbank, Sandy Cay, has become a growing flashpoint following a series of encounters between Chinese and Philippine coastguard, military and fishing vessels. The Philippines said the Chinese-flagged research vessel Xiang Yang Hong 33 had been spotted near the reef on Saturday, escorted by two coastguard ships. Jay Tarriela, a spokesman for the...