Puerto Rico police are investigating whether a man accused of murdering a pregnant US tourist this month may have killed two children nearly two decades ago, authorities said Wednesday. Eliezer Marquez Navedo has been charged with slitting the throat of California native Sara Kuszak three weeks ago. Authorities now wonder whether he may have been behind the deaths of the two toddlers, ages 2 and 3, in 1992 - a crime for which his mother was convicted. She was sentenced to 26 years in prison but paroled for good behavior after seven. Police plan to question Marquez again and analyze the victims' wounds for any similarities, investigator Arsenio Rodriguez said.