Authorities say carbon-monoxide poisoning is suspected in the deaths of two Elsberry couples.
Bodies of the four people were found by friends Sunday in a houseboat on the Mississippi River near the Illinois shore in Calhoun County.
The carbon-monoxide apparently leaked from an aging generator, Illinois authorities said Tuesday.
The 35-foot boat was equipped with a carbon-monoxide detector that could have warned the victims of a buildup of the colorless, odorless and often toxic gas, but the device had no batteries, said Chris McCloud, a spokesman for the Illinois Department of Natural Resources.
The leak is the likely culprit in the deaths of Jody Ryan and her newlywed husband, Dale, and her brother, William Boehm and his wife, Ruth.
Authorities say the four had been partying on an island near Hamburg in early celebration of Jody Ryan’s 39th birthday. Funeral arrangements are pending.
The Associated Press contributed to this article.
