Friends of missing Manhattan school teacher Hannah Upp say it is unlikely she ran away or left the area willingly.

Upp's friends and roommate told FOX News on Sunday that the 23-year-old teacher left her personal belongings behind in the her apartment — including her purse, wallet, and cell phone — and did not indicate that she planned to leave town.

They said Upp was excited to begin her second year of teaching at Thurgood Marshall Academy in East Harlem, N.Y.

Authorities and a teachers' union are offering rewards for help finding Upp who disappeared just days before classes began.

The United Federation of Teachers announced a $10,000 reward Friday, adding to a $2,000 reward offered by the New York Police Department's Crime Stoppers unit.

Police say Upp was last seen about 2:30 p.m. Aug. 29 as she left her apartment in the Hamilton Heights neighborhood.

FOX News' Laura Ingle and The Associated Press contributed to this report.