The CEO of online book retailer Dangdang.com blasted Morgan Stanley Monday, accusing the investment bank of significantly undervaluing his company in its initial public offering.

"I am publicly criticizing investment banks, criticizing Morgan Stanley," Li Guoqing, chief executive of Dangdang.com, wrote on a microblog-ging service similar to Twitter on Internet portal Sina.com.

He criticized the bank by name after posting an angry rant in a Chinese rap style with lyrics railing investment bankers, saying they were celebrating while he was furious when the company was valuated.

His profanity-laced rap drew more than 2,600 comments in less than 24 hours.

Dangdang, co-founded by Li's wife and the firm's chairwoman Peggy Yu, raised $272 million last month by selling a total of 17 million Ameri-can Depositary Shares at $16 a piece, a price above its revised $13-$15 range, according to Dow Jones Newswires. Morgan Stanley and Credit Suisse were the leading underwriters for the listing.

Despite Li naming Morgan Stanley, Dangdang's public relation's department said the rap lyrics were "not aimed at any specific company or person" in an apparent effort to play down the rant.

"These comments are offensive, highly unprofessional and do not reflect industry practices. We condemn such behavior that can risk damaging a company's brand and reputation," the bank said in a statement.