The German authorities ordered the area to be sealed and cleaned, and say that there is no wider risk of contamination.

Ed Sheeran's multi-million selling album ÷ has been excluded from the main categories at the 2018 Grammy Awards, surprising many industry observers.
The star was edged out of contention by Bruno Mars and Kendrick Lamar, who each received multiple nominations.
Jay Z leads with eight nominations, including his first ever appearance in the album of the year list for 4:44, which comes 21 years after his debut.
Sheeran did receive several nominations in the pop categories, however.
Shape of You is up for best pop solo performance, while ÷ is shortlisted for best pop album.

Lady Gaga is also relegated to the pop categories for her recent album, Joanne, while Katy Perry fails to receive any nominations at all.
Overall, the shortlist is very male-dominated, with New Zealand's Lorde the only woman cited for album of the year.

Taylor Swift also missed out on a nomination for her single Look What You Made Me Do, one of the most talked-about records of the year.
Her recent album, Reputation, was released too late to be eligible for an award - but the star does receive recognition for writing Little Big Town's single Better Man, which is up for best country song; and for her duet with One Direction's Zayn Malik, I Don't Want To Live Forever, which featured on the Fifty Shades soundtrack.
Jay Z's haul comes in recognition of his 13th studio album, which finds the star in a vulnerable, reflective mood. The title track confronts his infidelity, while the self-lacerating Kill Jay Z discusses how fame inflated his ego.