Hong Kong emergency crews worked around the clock with robotic “water-pumping dragons” to clear widespread flooding in the northern New Territories after intense downpours triggered a brief red rainstorm warning early Thursday.The Hong Kong Observatory issued the red rainstorm signal at 2.40am as intense showers battered the city, following an amber warning that had been in force since 9pm on Wednesday and a flooding alert for the northern New Territories.It said heavy showers and squally...