A direct manual trade of 6.46 million shares of CCB (00939) was registered at 11:28a.m.
The deal amounted to HK$36.24m, or at HK$5.605 per share, 6.2% higher than previous close.
CCB is now trading up 6.25% to HK$5.61, with 1.16 billion shares of HK$6.4b changing hands.