BBC report on Germany explosion - Mayor says 'explosive device'

I had the headlines on this a few hours ago: Explosion kills one in restaurant in German city

Last I heard it was a gas leak

But the BBC report:

• The cause is unclear although the city's mayor is quoted as saying it was an "explosive device".

That's not good.

More (Reuters):

• Spokesman for the Bavarian Interior Ministry said the explosion was not an accident and appears to have been intentional

More:

• Police saying the person killed in the explosion was the bomber, in a suicide vest
• A nearby music festival has been evacuated