Four out of six animal rights protesters descended to the ground Friday after staging a four-day "sit-in" atop a towering construction crane at the University of California campus after a court ordered them down.

Two others remained atop the 10-story crane in defiance of an Alameda County Superior Court order mandating that the demonstrators come down.Police booked the four demonstrators who descended only on trespass charges, but warned that the two protesters who remained aloft were guilty of contempt of court.