* HSI +0.2 pct, H-shares -0.4 pct, CSI300 +0.1 pct
* Sinopec plumbs new lows as Qingdao blast probe escalates
* Ningbo-related counters extend gains on trade zone hopes
* Chow Tai Fook flat ahead of interim earnings
HONG KONG, Nov 26 (Reuters) - Shares of Chinese energy giant Sinopec Corp slumped early on Tuesday after police detained nine people in connection with the blast on its Qingdao oil pipelines, weighing on benchmark indexes in Hong Kong and China.
By 0330 GMT, the Hang Seng Index was up 0.2 percent at 23,728.9 points, while the China Enterprises Index of the top Chinese listings in Hong Kong slipped 0.4 percent.
At the midday break, the CSI300 index of the leading Shanghai and Shenzhen A-share listings was up 0.1 percent, while the Shanghai Composite Index was flat.
"At this point, I still don't think the Qingdao accident will be too much of an impact on Sinopec's earnings, so the moves are really more psychological than anything else," said a Shanghai-based trader at a major Chinese brokerage.
China Petroleum and Chemical Corp (Sinopec) fell 2.8 percent in Hong Kong and dropped 1.4 percent in Shanghai, to their lowest in more than a week.
Seven of the detained worked for Sinopec, which owns the pipeline, and two were from the city's economic and technological development zone, the Xinhua news agency said late on Monday, quoting police.
The blasts forced Sinopec, Asia's top oil refiner, to cut production for at least two of its refineries in China's eastern Shandong province, according to industry sources. Oil traders also expected Sinopec to cut back on crude purchases while a backlog of tankers outside one port clears.
Companies seen related to Ningbo extended strong gains on hopes for approval of a free-trade zone covering the coastal Chinese city in the eastern province of Zhejiang and the nearby Zhoushan Island.
In Shanghai, Ningbo Marine surged by the maximum 10 percent and Ningbo Port spiked 9.8 percent, while Ningbo Fuda jumped 9.6 percent and Ningbo Construction 7.9 percent.
Chow Tai Fook inched up 0.3 percent ahead of its interim earnings for the six months ended Sept. 30. Down 0.6 percent on the year, Chow Tai Fook is currently trading at 16 times forward 12-month earnings, a 10 percent premium to its historic average, according to Thomson Reuters StarMine.
In the last 30 days, 9 of 27 analysts who cover the stock raised their full-year earnings-per-share estimates by an average of 10.2 percent, according to StarMine.
YuanShengTai Dairy Farm, China's fourth-biggest raw milk producer, fell 1.6 percent on its Hong Kong trading debut after raising $425 million in the second initial public offering by a dairy company in the city in two months.