SPENCER, NE — Officials say a dam in north central Nebraska has been compromised.

Authorities with the National Weather Service and the Nebraska State Patrol say the dam was compromised sometime after five P-M Wednesday. This video shows the Niobrara River pouring through gaping holes in part of the dam.

Mandatory evacuations are underway in communities downstream of the dam in Boyd and Knox Counties. Reports say the swelling river has taken out the bridge next to the dam on Highway 281, the Highway 11 bridge south of Butte, and the Redbird bridge south of the Niobrara in Holt County.

Reports say the Spencer Dam is 91 years old and was formerly used to generate hydroelectric power.