Dozens of agencies have been called in for help in the search for a missing 75-year-old woman who wandered from her Orange County home early Wednesday morning.

Authorities said Maryanne Rosenman left her home near Turkey Farm Road just outside of the Chapel Hill town limits between 4 a.m. and 6 a.m. Wednesday. A Silver Alert was issued at 12:35 p.m. Emergency officials said Wednesday afternoon that Rosenman has dementia.

An update by authorities on Thursday afternoon said that 991 acres had been covered in the search for Rosenman. Twenty-five different agencies and 180 people, including several K-9 units, have been searching in Orange County for the missing woman.

Rosenman is described as between 5 feet 4 inches and 5 feet 7 inches tall with a medium build and blonde, slightly curly hair.

Authorities said it was “very out of character” for her to have left her home at that time of morning. She was last seen wearing a blue nightgown and gray tennis shoes.

Authorities said at a press conference Wednesday afternoon that a motorists called 911 shortly after 3:20 a.m. Wednesday saying that an individual matching the description given for Rosenman was walking along Whitfield Road.

Emergency officials are asking residents in the area to check out buildings on their property in case Rosenman wandered into those areas. Sheriff’s office spokeswoman Alicia Stemper said that authorities are grateful for the outpouring of public support during the search.

Anyone who sees Rosenman or heard something suspicious in that area of Orange County early Wednesday morning is asked to call 911.

Photo via Orange County Sheriff’s Office