(CNN) -- An Ohio judge on Tuesday set a $1 million bond for the man accused of kidnapping and keeping a 13-year-old girl bound and gagged in his basement, authorities say.
Matthew Hoffman, 30, is suspected of having abducted Sarah Maynard, who authorities discovered over the weekend. She disappeared on Wednesday along with her mother, brother and family friend.
Sarah Maynard's mother, Tina Herrmann, 32, remains missing, along with 10-year-old Kody Maynard and Herrmann's friend, 41-year-old Stephanie Sprang.
Hoffman appeared in the Mount Vernon Municipal Court on Tuesday via a video link with the local jail, according to Pam Fuller, a deputy clerk. He is represented by a public defender.
Hoffman sat in a corner and looked straight ahead during much of the proceeding. He wore what looked to be a green vest, which the local sheriff later described as a suicide gown.
Knox County Sheriff David Barber said Hoffman was put in the gown after he gave indications to the jail staff and to investigators he could try to harm himself.
Previously, Barber has said he believes Hoffman could "absolutely" lead police to the three missing people. He is not cooperating with the investigation, officials said.
"The likelihood is, of course, that they are not alive," Barber said about Herrmann, her son and Sprang.
But he added he hopes they are, and that the department's priority remains trying to find them.
Sarah Maynard was released from the hospital Monday. Barber described the girl as doing well under the circumstances.
"There's so many people behind her that definitely that's going to help with her emotional recovery. And she is receiving those kind of services as well," he said.
The sheriff asked members of the public to think back to last week, to what they may have seen, and to call a tip line with any information.
"Wherever the investigation leads us, that's where we're going," he said.
The next hearing in Hoffman's case is scheduled for November 23. Authorities have said they expect additional charges.