Sheriffs in Bedford County in Virginia say there have been major developments in the 40-year-old disappearance of the Lyon sisters.
Prosecutors and police will hold a news conference on Wednesday at noon in Wheaton, Maryland near where Sheila and Katherine Lyon vanished in 1975. They have refused to say anything on the record until they make their announcement.
A special grand jury in Bedford County has been investigating the girls' disappearance since last October and they have been looking hard at two men -- Lloyd Welch and his uncle, Richard. Both have been named as persons of interest in the case.
So far, Richard Welch's wife is the only person charged in connection to this case. On July 7, she was indicted on a felony perjury charge for lying to the grand jury.
On February 11, 2014, Montgomery County police held a news conference to announce investigators had enough evidence to call Lloyd Welch, a convicted sex offender, a person of interest in the disappearance of the Lyon sisters. They vanished from what was then known as Wheaton Plaza in March of 1975.
As the case progressed, investigators revealed in a court affidavit that Lloyd Welch admitted leaving the shopping center in a car that day with the girls, his uncle, Richard Welch, and a juvenile. He then said the last time he saw the sisters was the next day at his uncle's house where one of the girls was being sexually assaulted.
Since then, investigators have searched the home of Richard Welch. Through his attorney and other family members, he has maintained his innocence.
Authorities have also spent considerable time on Taylor's Mountain in Thaxton, Virginia looking for the girls' remains. On the day the search began, Bedford County Commonwealth's Attorney Randy Krantz held a news conference with the sheriff.
"When you have an operation of this nature, one of the things you have to keep in mind is what your mission is," said Krantz. "You have to maintain mission focus and our mission focus is to bring these children home if at all possible. This case will be resolved."
The Lyon sisters were 10 and 12 years old at the time of their disappearance and had walked to Wheaton Plaza to eat pizza and look at Easter decorations.
A records check shows Lloyd Welch is still in prison in Delaware and no publicly available documents show any new charges or arrests in the case.
For reasons that have yet to be explained, police and prosecutors are planning on holding two news conferences -- one in Wheaton, Maryland and one on Thursday in Bedford County in Virginia.
If indictments have been handed down by this grand jury, they are under seal and unavailable.