LinkedIn, the networking site for professionals, has been blocked in China after a user posted comments in support of Tunisia’s Jasmine revolution spreading to the country.

Many users in China are reportedly unable to access the site, which could be accessed on Thursday morning. Some users said the site was accessible via different routes than the normal one.

On 23 February, a LinkedIn user identified as "Jasmine Z" started the "Jasmine Voice" discussion group that was intended to discuss pro-democracy protests in the Middle East.

Jasmine Z wrote, "After years of independent thinking, I am becoming a critical dissent dying for democracy, freedom and justice in my homeland."

Other posts went on to criticise the autocratic one-party system and called the ruling communist party as "a power and elite club."

LinkedIn spokesman Hani Durzy has confirmed the blockage in an e-mail statement, saying the move appears to be part of a broader effort in China going on right now that included other sites as well.

Durzy said, "The company will continue to monitor the situation."

Since 2009, China has blocked sites such as those operated by Facebook and Twitter that do not comply with Chinese rules to filter politically sensitive information.

This time, the blockage comes when there have been detentions in China after an overseas Chinese-language website, Boxun, spread a call for "Jasmine Revolution" in the Asian country.

LinkedIn — which recently surpassed one million users in China — is planning an IPO to raise up to $175m.

Earlier this month, Secretary of State Hillary Clinton had said the US will support global Internet freedom.