The Mendocino County Sheriff’s Office is investigating after a woman’s body was found in the Russian River south of Ukiah. The discovery was made by a kayaker on Sunday, but was not announced by authorities until Tuesday. Police say the body was in a state of advanced decomposition, indicating it had been in the water for quite some time. The woman has not been identified and the cause of death is not clear. Investigators say there are no signs of external trauma.