A Syrian man who had been denied asylum in Germany set off an explosive device near a music festival in the center of the city of Ansbach late Sunday, injuring at least 12 and killing himself, officials said. 

Bavarian Interior Minister Joachim Herrmann said the 27-year-old man’s request for asylum was rejected a year ago, but he was allowed to remain in Germany because of the situation in Syria.

“We don’t know if this man planned on suicide or if he had the intention of killing others,” he said late Sunday.

The nearby open-air concert with some 2,500 in attendance was shut down as a precaution after the blast, Sky News reported.

The city’s mayor, Carda Seidel, told local media that an “explosive device” blew up in the city center but provided few other details.

Germany has been on high alert following a series of incidents in recent days.

On Sunday, a Syrian refugee wielding a machete killed a woman and injured two other people in the German city of Reutlingen. The 21-year-old man was apparently acting alone and was arrested by police.

One Friday, nine people were killed in a shooting near a shopping mall in Munich, which was carried out by an 18-year-old who later turned the gun on himself. 

The Associated Press contributed to this report.

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