Skirmishes between China and Vietnam.

https://www.nytimes.com/2017/06/21/world/asia/china-vietnam-south-china-sea.html

General Fan from China left the meeting with Vietnam because he received intelligence that Vietnam and USA were conducting oil exploration in Nansha while he's in Vietnam which was tantamount to a backstab on General Fan.

Who wouldn't be fuming?  The meeting was supposed to defuse the tension but Vietnam did exactly the opposite when General Fan arrived in Vietnam.

Both sides should adhere to the agreed codes of conduct and defuse the tension or there won't be peace in South China Sea.

Our late Lee Kuan Yew was wary of Vietnam in the past and was the first PM in the world to write to the Thailand King to warn about Vietnam.  Moreover, our late Lee Kuan Yew was also the one who encouraged the USA to contain Vietnam which resulted in the Vietnam war because Lee Kuan Yew didn't want communism to spread to South East Asia.