Protesters were in the middle of I-35W, holding hands and signs, some sitting on the ground. Police have arrested several of them.
VIDEO: Girlfriend posts gruesome aftermath of Minnesota police shooting
There were reports of the people in the surrounding area chanting from the highway overpasses.
The shooting of Castile by police sparked outrage across the nation, with his girlfriend capturing the aftermath on Facebook Live.
About 15 trooper vehicles were on the highway, with police standing by as protesters are moved off the highway.
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#breaking protestors block off highway in Minnesota. Live images on @abc7newsbayarea at 6:30 pic.twitter.com/w8qCIkRjVQ
— Jessica Castro (@JessicaABC7) July 13, 2016
UPDATE- woman taken into custody in Minneapolis protest LIVE on @abc7newsbayarea
— Jessica Castro (@JessicaABC7) July 13, 2016
Traffic reportedly backed up 3mi pic.twitter.com/sBgnzbsrZI
VIDEO UPDATE: protestors being arrested in protest in Minneapolis,MN on interstate 35. @abc7newsbayarea pic.twitter.com/WkepNcXP0n
— Jessica Castro (@JessicaABC7) July 13, 2016