WATERVILLE, Maine — The police chief leading a search for a missing 20-month-old girl says investigators believe someone took her from her father’s home.

The comment by Waterville police Chief Joseph Massey Monday marks the first time he has said directly he doesn’t believe Ayla Reynolds left her home by herself.

Ayla had been living with her father, who reported her missing Dec. 17. He told police he last saw her when he put her to bed the previous night at his home in Waterville. The home has been sealed with crime scene tape.

Massey spoke Monday when he announced a $30,000 reward is being offered for information leading to Ayla’s whereabouts.

Maine Public Safety spokesman Steve McCausland says it’s the largest reward ever offered in a Maine missing-person case.