DOVER, N.H. — A former bus driver in New Hampshire and Maine already sentenced to prison for sexually exploiting children has been sentenced to 50 years for sexually assaulting children on his bus.

John Allen Wright, who lived in Milton, pleaded guilty to sexually abusing two young special needs boys in his care. Fosters Daily Democrat reports he was sentenced on Monday.

In February, Wright was sentenced to 160 years for one count of possessing child pornography and five counts of sexual exploitation after he was arrested in September 2011 and charged with filming child pornography on the bus using cameras hidden in glasses and pens.

Authorities started investigating after they say Wright, who had worked for Provider Bus Service since 2008, traded child pornography images on the Internet.