A worker at Durham Passport Office has admitted stealing 30 photographs of girls from applications and making indecent images of children.
James Close, from Shildon, County Durham, stole the photos between May and December last year, Newton Aycliffe magistrates were told.
The 36-year-old also admitted possessing extreme pornography.
He was bailed ahead of a sentencing hearing at Durham Crown Court to be held on 22 November.
Close was told he would have restrictions on his use of computers as a condition of bail.
After the hearing a spokesman for Durham Police said: "Following intelligence received, a warrant was served at an address in Shildon in County Durham earlier this year and a number of items were seized by officers.
"As part of that investigation a man was arrested at his workplace in Durham City on suspicion of possession of indecent images of children and theft from his employer."