Dec 8 (Reuters) - Sculptures of George Floyd and Breonna Taylor - two of the Black Americans killed at the hands of police in 2020 - are to be auctioned to aid the non-profit groups set up by their families. Sotheby"s auction house said on Wednesday that the sculptures by artist Chris Carnabucci will be offered for sale at its Dec 9-17 online auction of contemporary art after going on public exhibition in New York City earlier this year. Floyd, who died in May 2020 after a white Minneapolis police officer knelt on his neck for over nine minutes during an arrest, became the face of a movement challenging police brutality and bias in the U.S. criminal justice system. The officer was sentenced to 22 years in prison. Taylor was shot and killed when armed police stormed her Kentucky apartment in March 2020. None of the officers has been charged with her death. Sotheby"s in New York said the 6 ft (1.8 meter) tall bronze painted sculpture of the head of Floyd was expected to fetch $100,000-$150,000. The Taylor work is of a smaller scale at less than 4 ft (1.2 meter) tall. It has been re-envisioned from the original bronze finish with black and white body art created by the Nigerian-bred performance artist Laolu. It carries a pre-sale estimate of $20,000-$30,000. Sotheby"s said proceeds from the sale will support the We Are Floyd and Breonna Taylor Foundation established by their families to fight for social justice.