Correspondent Priya David Clemens reported on "The Early Show" that the search for evidence around Kyron's elementary school has intensified in recent days.
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And now, Clemens said, there's word a second person may have been waiting in Kyron's stepmother's truck on June 4, the day he went missing. Investigators wwer expected to ask for the public's help today in identifying that second person.
At least two witnesses have told police they saw a second adult waiting in Terri Horman's truck while she was with Kyron at his school science fair the day he disappeared. Investigators are looking for witnesses to confirm the claim and offer a valid description.
Bruce McCain, former captain of the Multnomah County Sheriff's Office, told CBS News, "The identity of that second person, if he or she existed, could be critical in determining what happened to Kyron after 9 a.m. on June 4."
The next day, while hundreds were searching for Kyron, Terri Horman was texting friends. In newly published e-mails, she wrote, "He was seen with a man 'chaperone' and two girls after I left."
She also lashed out at bloggers who were blaming her, saying, "I just want to scream." In another text, she describes Kyron as "acting really weird. ... The doc thinks that he is having mini-seizures, and I made an appt. ... for next Friday to have him checked out."
That contradicts school officials, who believed Kyron was going to the doctor the day he vanished.
McCain said, "It's all about Terri, poor, poor Terri, and not a single concern about Kyron. She's already making alibis, talking about a chaperone and on and on about doctor's appointments."
Police are also distributing new fliers in their search for clues. For the first time, photos of Horman's close friend, DeDe Spicher, are included, along with an attached questionnaire asking if anyone saw Spicher near the school that day. She says she was on a gardening job, but her employers now claim they were unable to reach her for four hours -- much longer than first reported.
Clemens added the grand jury is continuing its investigation. On Tuesday, they met with employees at a coffee shop where Terri Horman says she was the morning Kyron disappeared. Clemens said it appears the grand jury is still trying to establish an exact timeline for Terri's whereabouts that day.
CBS News Legal Analyst Jack Ford said on "The Early Show" the news conference today will likely reveal just a few details the police hope may jog people's memory.
"Generally speaking, if you're investigating a disappearance, or any kind of criminal case, you always want to hold back some facts. You don't want the public to know everything you know. Because if someone comes in and wants to confess, you can use that as a gauge. Do they know details that nobody else knows but you as an investigator? But sometimes, you have to sort of feed some of them out slowly if you're not making headway. We're more than two months from his disappearance."
Ford said a request for the public's help is indeed likely at the press conference.
As for the grand jury, Ford said at the end of the day, it may not charge anyone in Kyron's disappearance. However, down the road, if new evidence is discovered, a new grand jury could be formed and people possibly charged.
What are the chances Kyron will be found after more than two months?
Ford said, "We've seen some cases, obviously, that have surprised us, where months and years have gone by and people who have disappeared all of a sudden are found. But again, generally speaking ... investigators will say the longer the time goes by, the more difficult it is to come up with a good and happy ending for a case like this."