Manassas, Va. (AP) — A plea deal for a Connecticut man accused of a series of rapes along the East Coast fell through Tuesday after the defendant told a judge he wasn't sure he knew what he was doing.

A plea hearing had been scheduled in Prince William County for Aaron Thomas, who is charged with abducting three teenage trick-or-treaters in 2009 in Virginia and raping two of them. But the deal was called off when Thomas, of New Haven, Conn., revealed hesitation.

At the outset of the hearing, Thomas told the judge in a barely audible voice that he wasn't sure what was right and what was wrong.

"I'm not sure I know what I'm doing," Thomas said.

The assaults were the last of 17 that authorities attributed to Thomas, who was linked through DNA and other evidence to assaults and rapes on women as far back as 1997.

Thomas was arrested in Connecticut in March 2011. His lawyers had pursued an insanity defense before dropping those plans and moving forward with a plea deal.

Prince William Commonwealth's Attorney Paul Ebert said Thomas had signed a plea agreement admitting guilt in two rapes and three abductions in the Halloween attacks. Ebert had agreed to drop three lesser firearms charges as part of the deal. Thomas would have faced up to life in prison under the deal's terms.

Ebert said after the hearing that he had hoped the plea deal would go forward to spare the victims from testifying at trial, but he's prepared to put on the case regardless.

In court, Thomas looked more alert than at previous hearings but kept his head down and his shoulders hunched forward. Court records indicate he had been behaving erratically, including cutting himself, behind bars.

Ebert said he was not surprised Thomas balked at the plea due to his odd behavior.

"He's an unusual character," Ebert said.