Microsoft Corp.’s search engine Bing was blocked in China due to an accidental technical error rather than an attempt at censorship, according to people familiar with the matter.

The government had no intention to block Bing but it’s unclear when the service will be restored, according to two people with knowledge of the matter who asked not to be identified discussing confidential information.

The Cyberspace Administration of China didn’t respond to faxed questions. Hua Chunying, a spokeswoman for China’s foreign ministry, deferred comment to “other relevant, competent authorities.”

“Some reports are saying it is due to technical problems,” she told reporters on Thursday. “You should ask other parties.”

A spokesman for Microsoft declined to comment beyond an earlier statement that confirmed Bing was inaccessible in China and that the technology giant was determining its next steps.

The incident highlights the risks faced by technology companies in China, where regulatory bodies frequently ban, block and even delete popular services for a myriad of reasons. More than 24 hours after Chinese users first starting having problems accessing Bing, the service was sporadically available for some users but still offline for others.

A move to block Bing would be surprising because Microsoft has sought to build a local operation on Beijing’s terms. Unlike Alphabet Inc.’s Google, which pulled its search engine out years ago in part to avoid government censorship, Microsoft has toed the line and stops content deemed illegal from showing up in results. Other internet products such as its Azure cloud computing service remained online and available, according to some of its customers.

The service block comes as Beijing ramps up its push to scrub the domestic internet, which it sees as a growing threat to social stability. Communist leaders face a year rich with sensitive dates, including the 70th anniversary of the country’s founding on Oct. 1 and the 30th anniversary of the party’s crackdown on democracy activists in Tiananmen Square on June 4. Such occasions have sometimes helped coalesce criticism of the regime, and China often rounds up dissidents in advance.

Microsoft President Brad Smith said the company wasn’t yet certain whether the Bing incident reflected a broader issue.

“It’s not the first time that we’ve encountered issues like this for being in China. These do arise periodically,” he told an audience in Davos. “We do adhere to the global network initiative set of principles when it comes to search services in China. And that does mean that there are days when there are either difficult negotiations or even disagreements, but we’re not aware of any ongoing negotiation or disagreement.”