SHANGAI: Shares in China's top search engine Baidu surged in after-hours trading today after Google vowed to defy China's Internet censors and threatened to pull out of the country. The Nasdaq-listed Baidu surged to 413.52 dollars per share in after-hours trade, up 6.99 per cent from yesterday's market close of 386.49 dollars in New York. The Chinese company declined to comment on Google's announcement when contacted. Google said it would no longer follow censors' directives to filter search results in China after cyber spies based there allegedly struck the Internet giant and other firms in a bid to hack into the email accounts of activists around the world. The alleged online espionage has led Google to reconsider its business operations in China, the company's chief legal officer David Drummond said in a blog post. In China, Baidu is the nation's biggest search engine with a 63.9 per cent market share as of end-September, ahead of Google China at 31.3 per cent, according to figures provided by Internet research firm Analysys International.