BERLIN (AP) — Police arrested a man suspected in a stabbing attack Friday at Berlin’s Holocaust Memorial that left a Spanish tourist seriously injured, police said.

There was no immediate indication of a motive for the attack, which comes two days before Germans vote in a national election on Sunday.

Police spokesman Florian Nath told a news conference that the attack happened at 6 p.m. “probably with a knife. Maybe with something else.” Nearly three hours later, a male suspect approached officer who had surrounded the memorial grounds. “He had blood on his hands and this made him very suspicious," Nath said.

Police arrested the man, handcuffing him and holding him on the ground. Nath said police seized the attack weapon and would interrogate the suspect as the investigation continued.

The victim was identified as a 30-year-old Spanish man, who was taken to a hospital.

The attack took place at the Memorial to the Murdered Jews of Europe, a field of 2,700 gray concrete slabs near the Brandenburg Gate in the heart of Berlin, which honors the 6 million Jews killed in the Holocaust under the direction of Nazi Germany.