KEY WEST, Fla. -

A former substitute teacher in the Florida Keys was arrested on Thursday on charges of possessing child pornography.

William Britt, 55, was charged with 123 counts of possessing child pornography and seven counts of possessing a photograph of a sexual performance by a child.

Britt reportedly taught at Horace O'Bryant Middle School, Sugarloaf School, Key West High School, Marathon High School, Poinciana Elementary School, Glynn Archer Elementary School and Gerald Adams Elementary School.

He was taken to the Monroe County Jail on Thursday on $145,000 bond.

Schools Superintendent Mark Porter said Britt had passed all background screening tests before being employed as a substitute teacher.

Becky Herrin of the Monroe Sheriff's Office said Britt's former landlord called police after he saw a box filled with child porn while helping Britt to move.