Photo taken on Aug. 27, 2019 shows the scenery of the Victoria Harbour in Hong Kong, south China. (Xinhua/Li Gang)

Out of the 2.9-percent gross domestic product slip in the third quarter in Hong Kong, over 2 percentage points were caused by the prolonged social unrest, a senior official of China's Hong Kong Special Administrative Region (HKSAR) government said Friday.

Hong Kong's economy dropped 2.9 percent in the third quarter, the first year-on-year negative growth since the global financial crisis in 2009, and was considered entering a technical recession after shrinking for two straight quarters, Financial Secretary Paul Chan said.

Violent incidents in the past few months impacted various industries and the global image of the financial hub, Chan said at a conference of the Legislative Council, stressing that Hong Kong experienced unprecedented turmoil.

Violent acts of rioters from blocking roads to vandalizing railways and shops have posed a major challenge to sectors including tourism, retail sales and catering, said Chan, adding the turnover of many shopping malls, restaurants and hotels have witnessed record-setting plunges.

"As the social unrest continues, the situation of those industries is worrying and can hardly improve," Chan said, adding that the local incidents, along with a global economic slowdown and the trade tension between major economies, continued to overshadow the growth prospects of Hong Kong.

In the face of the situation, the HKSAR government has announced four rounds of relief measures for embattled businesses and residents since August, worth 25 billion Hong Kong dollars (3.19 billion US dollars) in total, he said.

Chan called for concerted efforts from various sectors of Hong Kong to stop violence and restore order and the rule of law so that the economy will be back on the growth track.