* SSEC +0.4 pct, CSI300 +0.5 pct, HSI +0.1 pct
* Financials bounce as c.bank injects medium-term funds
* Shanghai shares poised for 5th straight week of losses
SHANGHAI, May 12 (Reuters) - China's main stock indexes extended gains on Friday morning, as the central bank's move to inject funds amid liquidity worries offered some solace.
The CSI300 index rose 0.5 percent, to 3,373.49 points at the end of the morning session, and the Shanghai Composite Index gained 0.4 percent, to 3,073.48 points.
Both indexes remained on track for a fifth straight week of losses amid persisting regulatory worries.
China's central bank injected fresh funds through a medium-term lending facility on Friday while keeping a tight rein on short-term funding. This appeared to be a further effort to dampen speculative investment while the economy remains adequately funded.
The central bank also issued a notice to banks to inquire about interest rates on inter-bank borrowings, loans and bill markets, the official Shanghai Securities News reported on Thursday.
Tight liquidity conditions have been a major concern for investors amid a crackdown on banks' risky financial activities with a focus on shadow banking.
In the morning, financial plays led gains, in particular bank stocks, whose index rallied 2 percent, positioning it for the best day since mid-August.
Authorities tended to maintain stability in the financial markets ahead of major events, such as a Silk Road summit this weekend.
However, there were no specific signs that the heavy hand of regulation would loosen.
China's banking regulator this week launched emergency risk assessments of lenders' new business practices, sources told Reuters, as Beijing deepens its crackdown on shadow banking.
"The tightening liquidity conditions and financial regulations would probably continue, and chances are small for authorities to reverse the shift to a tightening bias," said Yan Kaiwen, an analyst with China Fortune Securities.
On Friday morning, Hong Kong stocks inched up, hobbled by a downbeat day on Wall Street but still on track for handsome gains this week.
The Hang Seng index added 0.1 percent, to 25,144.57 points.
The Hong Kong China Enterprises Index gained 0.2 percent, to 10,273.06.
($1 = 6.9014 Chinese yuan)
(Reporting by Luoyan Liu and John Ruwitch; Editing by Richard Borsuk)