Google’s services were blocked again in China today after a temporary respite yesterday, reveals reports by users, continuing more than a month of severe disruption.

Chinese users have not been able to use Google’s services such as search, maps, online advertising services, and emails for over a month now, in the run-up to the 25th Tiananmen anniversary.

Users say there was a brief respite yesterday as the US Secretary of State John Kerry came calling for joint discussions, where cyber-security was high on the agenda.

A twitter user even thanked Kerry yesterday by tweeting," Google’s unblocked today! Thanks, Kerry, do stay."

But the Chinese anti-censorship group GreatFire.org reported that the services seem to work because "Great Firewall", the tool used by the Communist Party to block websites, experienced a glitch.

"It looks like merely a bug of the Great Firewall," said a member of the group who used a pseudonym. "It’s blocked again."

Google has not commented on the matter yet.

Disruptions were also observed in other online services since last week, including South Korean mobile messaging apps – Naver Corp’s Line and KakaoTalk; Yahoo Inc’s photo-sharing site, Flickr; and Microsoft Corp’s OneDrive cloud storage platform.

China exercises tight control over the Internet and often limits access to some websites based outside the country ahead of sensitive anniversaries or political meetings.

Google’s services were always accessible intermittently in the country. The company, in fact, shifted its China-focused search operations to Hong Kong — a special administrative region of China where the mainland censors doesn’t apply — in 2010.

Other overseas online services, such as Facebook, Twitter, and Google-owned video site YouTube, have also been blocked in China.