Dissatisfaction among Astrill's Chinese users continued Monday as the virtual private network (VPN) company called its users in China "stupid" for spreading news of Astrill's new software on the Internet and blamed them for its service interruption during the Spring Festival holiday.

Astrill users in China began to receive notices about service interruptions on February 5, three days ahead of the lunar new year.

According to users, the VPN service was intermittently inaccessible during the seven-day holiday that began on February 7.

In an Astrill notice posted online by one of its users, the company said some users were "not that smart and helping Chinese censors by spreading news about new Astrill software all over the Web" while engineers tried to fix problems with its iOS app.

"We can invent new technologies ... but we don't have a solution for stupidity. Dear 'journalists,' please spread this message as usual, all over the Web and join DUMB CLUB," it said.

Though the company later posted another notice arguing that it was not targeting Chinese customers, the comments stirred up criticism among Astrill users in China.

Some netizens complained on Facebook about the US-based company's impolite attitude and demanded a refund. Others said the company should shoulder greater responsibility instead of blaming customers.

Some netizens said on Chinese online community Baidu Tieba that they would become anti-Astrill because of the "insulting" notice.

The company said it would offer free service to every customer affected during "Chinese holidays," including two weeks of free service and 30 days of Stealth VPN add-on use.

The company could not be reached for comment by the Global Times as of press time.

VPN services in China often report alleged access problems during holidays and at the year's end. Astrill notified its users last August of possible limited access due to a military parade in Beijing on September 3, 2015.