The dead, a 53-year-old man and two women aged 33 and 30, were all German citizens.
Arrows were found in the bodies of three people found dead in the southern German city of Passau on Saturday, police confirmed.
Their bodies were found at the hotel on Saturday morning by an employee who opened the door to their three-bed room when they did not respond to repeated knocking.
There was no sign of a fight, nor of another participant, police said.
The latest macabre finds were uncovered in the north German town of Wittingen, while detectives probed the mysterious deaths of a man and two women discovered over the weekend in the Bavarian town of Passau, close to the Austrian border.
Biden clears Route for campaign staff to Arrange union
And it appears to be working - Trump when the former vice president was endorsed by the International Assocation of Fire Fighters. A Monmouth University survey of New Hampshire voters show Biden is favored by 36% of voters.
Local media reported that the man and the 33-year-old woman were found dead in bed holding hands, with bolts in their heads and chests.
The three arrived in the evening the day before the tragedy and reportedly wanted to stay three nights without breakfast. Hunting with bows or crossbows is banned in Germany. Results of an autopsy are to be made known on Tuesday.
"It was a completely quiet night", another of the hotel's guests told Passauer Neue Presse (PNP), adding that she had not seen any suspicious activity.
A police spokesperson confirmed that the two corpses in Wittingen, Lower Saxony, had not been killed by crossbow bolts, "the modus operandi can not be compared". It was registered in Westerwald, Rhineland-Palatinate. The second woman was found in a pool of blood on the floor.
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. One of the victims in the Passau deaths, a 30-year-old woman, lived in Wittingen, according to prosecutors.