SINGAPORE - Sembcorp Marine said on Tuesday (Jan 23) it is "unaware of any information not previously announced" that would explain the active trading in its shares.

"The company has noted various reports in the media and rating upgrades by stock broking firms in the last one week that might have an impact on the share price. The company is not aware of any other possible explanation for the unusual trading activity," it said.

Shares of the oil-and-gas firm rose 12 Singapore cents, or about 5 per cent, to S$2.51 as at 11.31am on heavy trading. Nearly 17 million shares changed hands.