Burglars got away with a pair of 5-carat diamond earrings valued at HK$7 million and another HK$1.7 million in cash and valuables after breaking into the Sai Kung home of a Taiwanese businesswoman and her husband who had gone out for dinner.
The alarm was raised shortly after 9pm on Sunday, and as officers were combing the area with sniffer dogs, a second call came in to report another burglary just 300 metres away.
Police believe both of the burglaries were carried out by the same team, with one burglar breaking in and a second acting as lookout.
Officers said the HK$8.7 million haul made it the biggest burglary to hit the coastal Sai Kung district in the past 12 months - with recent months seeing a spate of burglaries in luxury homes throughout the city.
Lin Jen-ni, 57, and her husband, Chiang Chih-chiang, 59, returned from dinner to their three-storey house in Lotus Villas, on Chuk Yeung Road, shortly after 9pm to find they had become the latest statistic.
As well as the HK$7 million earrings, three luxury watches, four other pairs of earrings, 100,000 yuan (HK$130,000) and US$5,000 were taken.
Initial investigations suggested that a burglar had shinned up a drainpipe and pried open the kitchen window on the first floor.
"Valuables and cash were mostly taken from unlocked drawers in the second-floor master bedroom," an officer said. The second report of a burglary in the area came just before midnight when a 27-year-old accountant returned to his two- storey home in Muk Min Shan Road to find it had been broken into and a HK$2,000 watch and HK$10,000 in cash missing.
"It is possible the two raids were carried out by the same gang," the officer said. "The raiders burgled the Muk Min Shan Road house but were not satisfied with the loot. They then climbed down a hill and raided the Lotus Villas house."
He said the burglars probably laid in wait to look for targets and struck after seeing them go out.
Another officer added that a break-in usually involved two burglars. "One of them acts as a lookout and the other sneaks into their targeted house to steal."
The Wong Tai Sin district crime squad is investigating.
The number of burglaries in Sai Kung rose from 100 in 2012 to 142 last year. "Most of the houses had not installed security measures or their tenants forgot to turn it on when they went out," said Paul Gordon, Sai Kung divisional commander.
The biggest single haul in recent months saw HK$20 million worth of jewellery taken from a home on The Peak in November.