Updated

A German official says the man who fatally stabbed one person and wounded several others in Hamburg was known to authorities as an Islamic radical but also was psychologically unstable.

The suspect, a 26-year-old born in the United Arab Emirates, was quickly overwhelmed by passers-by and arrested after Friday's attack in Hamburg's Barmbek district.

Hamburg's state interior minister, Andy Grote, said the man — whose asylum claim had been rejected — was known to have been radicalized but hadn't been considered dangerous.

Grote said the man's motive remained unclear Saturday, but he is believed to have acted alone and not been linked to an extremist network.

The man stabbed at least five people besides the one who was killed. Grote says none of the survivors' wounds are considered life-threatening.