The flat in Wittingen had been occupied by a 30-year-old woman who was one of the victims found in the hotel room.
German police are investigating the freakish deaths of three people killed by a crossbow in a hotel room in Bavaria.
The bare facts of the narrative have been established.
The 30-year-old woman - found in a pool of blood on the floor with an arrow through her chest - is reportedly the sister of one of the Wittingen women.
Two of the weapons extinct within the killings had been found on Saturday, whereas a third became as soon as found unused in a ranking on Monday, in response to police.
The other two discovered in that hotel room, a man and a woman, were found hand-in-hand, impaled with multiple crossbow bolts.
Forensic police officers were combing both crime scenes on Monday for clues.
Three people were found dead with crossbow injuries in the hotel.
One of the women is reported to have booked the triple room for 85euros a night, for three nights.
The group left an impression on other guests, with the man wearing a formal suit and sporting a long white beard and his female companions dressed entirely in black.
"It was a odd group", a guest recalled, according to the newspaper Bild.
Police are not looking for anyone else in relation to the deaths and post-mortem examinations have been ordered.
An autopsy should provide further information on the circumstances of death and the results should be available on Tuesday, the Passau public prosecutor's office announced on Monday.
According to a spokesman for the German Shooting Federation in Wiesbaden, anyone over the age of 18 can purchase a crossbow in Germany, the news agency DPA reported.