UNC police said they caught four people in the act of tipping over one of the sculptures on Franklin Street early Friday,
The vandals managed to rip off the "cow house" off of the fiberglass bovine.
The sculpture is worth an estimated $7,000 to $10,000.
Two people were arrested at the scene -- 22-year-old Ryan Tyson and 21-year-old Ryan Bradley. Two others ran away.
It was the second case of cow vandalism in Chapel Hill.
Earlier this week, someone ripped the bow-tie off of the "Alexander Moo-lian Bow-Vine" sculpture.
The cows are part of a three month exhibition.
Eventually, the cows will be auctioned with the money going to the N.C. Children's hospital.