Twitter has been experiencing some problems over the last few days. Many users found they couldn’t access the site for around ten minutes yesterday and on Friday, but things have got even worse for the microblogging service - it has been inaccessible via the web and mobile for almost two hours.

The issue is thought to be affecting users many - but not all - regions worldwide, although areas outside the US seem to be having the most issues. Reports started coming in from Western Europe that the site was down at around midnight PT. People trying to access Twitter on the web, mobile, and its API were met with error messages warning them that the network is both “over capacity” and suffering an “internal error.”

Twitter’s own service board has since confirmed the problem. “Some users are currently experiencing problems accessing Twitter. We are aware of the issue and are working towards a resolution,” the company posted in an update.

The company’s developer-facing monitoring confirms that four of the five public APIs are experiencing either ‘performance issues’ or ‘service disruption.’

Twitter initially confirmed the outage with a tweet from its @support account. Although most people probably never saw this, as they couldn’t access the site.

The number of outages over the last few days has brought back memories of Twitter’s early days when such issues were common. The constant “over capacity” warning became known as the fail whale, referring to the illustration of a white beluga whale held up by a flock of birds that accompanied the message.

It seems that now, just over two hours after the frist reports started coming in, Twitter is back up (although there still seems to be some issues with images and searches). The company hasn’t said whether the problem was due to a technical fault or caused by outside factors, but some have speculated that the length of time the site was down, coupled with the number of outages it has experience over the last few days, could suggest a cyberattack of some form.