Ffrom the Associated Press:

Police arrested 35 people for trespassing during a protest of frack sand mining in Winona.

The Winona Daily News reports officers on Monday arrested 19 people at the city's commercial dock and then responded to a sand processing plant on Winona's west end, where another 16 people were arrested.

Winona Catholic Workers organized the protest. Protesters say their goal was to halt business operations at each site.

Dan Nisbit, owner of CD Corp., which leases the commercial dock, says the protest created a distraction for workers and temporarily slowed operations at the facility.

Frack sand is used by oil and gas drilling companies. Opponents of frack sand mining have raised environmental concerns.