Salt Lake City police are investigating a murder after a woman's body was found floating in the Jordan River.

However, police said they have more questions than answers right now. Homicide detectives don't know who the woman is and aren't saying how she died.

"Once we're able to make that identification as to who she is, we can trace where she's been," Salt Lake City police detective Jeff Bedard said Thursday. "But until we know who she is, we can't do anything."

At about 4 p.m. Wednesday, two children playing by the Jordan River near the Utah State Fairpark spotted the woman's body floating in the water. She is described as white and appeared to be in her 20s.

"It's cold and frozen water," Salt Lake City Police Lt. Gary Young said. "They didn't know how long she's been in there."

There was no obvious cause of death, Young said. The woman's body is undergoing an autopsy at the Utah State Medical Examiner's Office.

"They're awaiting results from the medical examiner to make determinations," Bedard said. "They're still trying to figure out how long she'd been in there."

Police were pleading for more information that could help them catch the woman's killer. A reward is being offered for a tip that helps solve the case. Anyone with information can call the Salt Lake City Police Department's Tips for Cash hotline at 801-799-INFO.