A man of Islamist background has been detained by German investigators probing blasts against a bus carrying players of Borussia Dortmund soccer club, the federal public prosecutor's office said on Wednesday.
It said investigators had searched the apartments of two suspects from Germany's Islamist scene and decided to detain one of them.
It did not say where the suspect was detained but added that a decision would be made on whether to seek a judicial arrest warrant against him.
The prosecutor said metal strips had been used in the explosive devices activated in the attack, which injured one player and is being treated as having a "terrorist background".
"The precise motive for the attack is unclear at present," the prosecutor's office said in a statement.