STARKE, Fla. (AP) _ Serial killer Ted Bundy took responsibility Sunday for two Idaho murders and as many as eight in Utah, continuing tearful 11th-hour confessions even though they failed to bring him an execution delay, officials said.

Utah authorities had suspected Bundy in the deaths of two women and the disappearances of three others in 1974 and 1975. But in a 1 -hour prison interview with a detective late Sunday, ''there was one incident where he mentioned eight,'' Sheriff Pete Hayward said in Salt Lake City.

''Bundy did elaborate on some of the cases, and of course they've all been tape-recorded and documents marked,'' Hayward said. ''We'll be looking at it very carefully, to see if what he told us matches up.''

Hayward said his investigator described Bundy as uncooperative at times, and that he seemed ''very tired, putting his face in his hands, and acting as if he was going to sleep.''

Idaho state Attorney General Jim Jones said his chief investigator met with Bundy for about an hour, and that the condemned prisoner described two murders he committed in Idaho about 1974 or 1975.

''One seems to be fairly possible. The other is tough to tell at this time,'' Jones said in Boise after speaking to investigator Russ Reneau by phone.

Bundy provided Washington state and Colorado investigators on Friday and Saturday with details of at least nine murders for which he has long been suspected but never charged. By Sunday, however, he became erratic in his promises as he met with attorneys, a friend and paralegals.

Bundy, 42, who is scheduled to die at 7 a.m. Tuesday, broke but rescheduled an appointment with the Utah detective and canceled a Monday afternoon news conference with 30 journalists, officials said.

''He's got visits scheduled with investigators from Colorado, Utah and Washington, some of them tonight and some maybe tomorrow, although we don't know about tomorrow,'' L.E. Turner, assistant superintendent at Florida State Prison, said late Sunday. ''He may not have time for all of them.''

Bundy, who has been on death row at the prison since July 1979, lost an appeal to the U.S. Supreme Court a week ago, and no other court he has turned to since has offered a reprieve.

Bundy's next step could be an appeal to Anthony Kennedy, the Supreme Court justice assigned to consider last-minute Florida death appeals. One justice may stay an execution pending review by the full court, but Kennedy favors the death penalty.

In talks with authorities over the weekend, Bundy, who grew up in Tacoma, Wash., confessed to killing at least eight young women in that state in 1974, said investigator Robert Keppel of the Washington attorney general's office.

Bundy also confessed to the 1975 slaying of Julie Cunningham, 26, a Vail, Colo., ski shop employee whose body was never found, said Vail Police Chief Ken Hughey.

Hughey said Bundy is convinced that the only way he will get to heaven is to confess.

''He's attempting to purge himself,'' said Colorado Attorney General Duane Woodard. ''It is part of his repenting.''

''The man is trying to save his life,'' Keppel told KIRO-TV of Seattle. He added that Bundy was shaken and tearful as he responded to questions from investigators.

Bundy had not previously admitted to any slayings.

Bundy scrapped his plan to hold a news conference apparently on the advice of his attorneys, said Richard Shelton, executive director of the Florida Press Association, which was coordinating the event.

Last week Bundy offered to trade information about other slayings for a delay in his execution, but Gov. Bob Martinez, who signed Bundy's fourth death warrant Tuesday, said he would not ''negotiate with a killer.''

''Bundy is welcome to talk all he wants, but he better say it by Tuesday morning,'' said John Peck, press secretary to Martinez.

Bundy, scheduled to die for the 1978 kidnap-murder of 12-year-old Kimberly Leach of Lake City, Fla., at one time was linked to as many as 36 killings and disappearances of young women in Washington, Colorado, Utah and other Western states. He was being questioned about the deaths of at least 24 women.

The law school dropout was visited Saturday by officials from Washington state and Colorado, said Paul Decker, assistant superintendent of Florida State Prison near this north-central Florida town, where Bundy is held.

Bundy's lawyers lost two more bids for a stay of execution Saturday. U.S. District Judge G. Kendall Sharp refused to issue a stay, and then a three- judge panel of the 11th U.S. Circuit Court of Appeals in Atlanta denied Bundy's appeal.

Diana Weiner, a Sarasota attorney who has represented Bundy in some civil matters, asked Washington state Attorney General Ken Eikenberry to request that Florida's governor delay the execution.

''I am not going to do it,'' Eikenberry said.

Thomas Leach, whose 12-year-old daughter was Bundy's last victim, nevertheless doubted the execution would proceed, saying, ''They ain't going to do nothing.''

Miss Leach disappeared from Lake City Junior High on Feb. 9, 1978. Her body was found April 7, 1978, in a hog shed along the Suwannee River.

''I think it's been dragged on for far, far too many years,'' said Bob Simmons, assistant principal at the school.

Bundy also has been sentenced to die for the murders of Lisa Levy, 20, and Margaret Bowman, 21. They were clubbed to death at a sorority house at Florida State University in Tallahassee.

Hughey said Bundy acknowledged killing Ms. Cunningham, who disappeared in Vail in 1975. ''Detectives believe the confession is indeed valid,'' he said, noting that Bundy's details about the victim, her clothes and the Vail area have been persuasive.

In talks with Keppel, Bundy confessed to the eight ''Ted'' murders in Washington state. Witnesses had reported seeing a charming young stranger who called himself Ted near where several victims disappeared.

For the parents of one victim, Central Washington University student Susan Rancourt, the confession helped write the final chapter to a tragedy.

''It's been an open wound for 15 years, and every time we think it's settling down, something happens,'' said Miss Rancourt's mother, Vivian Rancourt, of LaConner, Wash. ''There will always be that loss that we cannot replace, but at least we can put it all together.''

Keppel said Bundy admitted to an additional Washington state killing, but the investigator was unable to say whether Bundy was telling the truth or just trying to buy time. Keppel, who earlier was quoted by KIRO Radio as saying three additional killings were discussed, said Bundy provided no further details.

Keppel said Bundy also confirmed the identity of one of the eight ''Ted'' victims as Georgann Hawkins, a University of Washington student who disappeared from an alley behind her sorority house in 1974. Her remains had never been officially identified.

Bundy's mother, Louise Bundy of Tacoma, told the Morning News Tribune of Tacoma that the confessions were unexpected ''because we have staunchly believed - and I guess we still do until we hear what he really said - that he was not guilty of any of those crimes.''

''But if this is true, if Ted did do these things, and if indeed he is substantiating it with facts that he really did those things ... it's the most devastating news of our lives.''