(NEW YORK) — The recent release of two credible ransom notes sent to Nancy Guthrie’s family in the days after her abduction generated a “slight increase” in tips, but none that have cracked the case, authorities told ABC News. On Friday, the Pima County Sheriff’s Department released details from two ransom notes received by Tucson media in the days after the abduction. The first note, sent on Feb. 2 to Savannah Guthrie, said, “We have your mother Nancy. The second note, sent on Feb. 6 to the Guthrie family, said Nancy Guthrie died and “is buried in nature now,” according to the sheriff’s department. In response to an inquiry from ABC News, the sheriff’s department said Tuesday that “investigators have seen a slight increase in tips since the two ransom notes were released,” adding that “all tips have been followed up on.”