At 1.47 am on Wednesday, a security guard working at Celestial Gardens found two strangers in the estate's parking lot. Suspecting that the two may attempt to commit a crime, he called the police immediately.

Police arrived later and checked the CCTV footage. Finding no suspicious person leaving, they believed that the men were still hiding in the estate.

The officers then noticed someone on the balcony of a renovated unit on the third floor and entered the unit to subdue and arrest the suspicious person.

At around 3 am, the police found another man climbing up along the gutter on an external wall.

To prevent him from falling when fleeing from arrest, they notified the Fire Department to stand by.

The man then climbed up to the balcony of a unit on the 16th floor. The police informed the residents to open the door and arrested him.

The preliminary investigation showed that the two arrested were illegal immigrants from Guangxi province and were believed to be members of a Guangxi burglary gang called the Wei's -- as most of their members have the Chinese surname Wei.