Update: The interruption lasted a few hours and varied in intensity.
Information from BGPmon: Massive route leak causes Internet slowdown
For information regarding BGP and how this could occour, we suggest reading Washington Posts article regarding BGP.
We experience operational disruptions on various servers because Telekom Malaysia (AS4788) is leaking faulty routes to a Tier 1 transit provider. This causes many ISPs to experience problems due to the wrong routes.
It is mainly our web server that has problems because it is Bahnhof that provides the internet connection to it.
External information:
https://www.bahnhof.se/kundservice/driftinfo#M3365042
https://mailman.nanog.org/pipermail/nanog/2015-June/076187.html
https://www.cloudflarestatus.com/incidents/bzknm1t91kjq