Clarkstown Police Chief Michael Sullivan says there could be more people involved in the killing of Rockland political activist Peggy Nadell.

Four women have been arrested in connection with the murder, including her own daughter-in-law, Diana Nadell.

Sullivan says the investigators are going to go where the evidence takes them. He says that while he's not anticipating more arrests, there could be more people involved.

The felony complaint says Nadell, who lives in Florida, and relative Andrea Benson, from Washington, D.C., travelled to Nadell's Spring Valley home on Jan. 25. The pair allegedly lured the 80-year-old to open the door and then beat and stabbed her.

Police say Eltia Grant, of California, and Tanisha Joyner, also of Washington, D.C., helped cover up the murder and were paid to provide Diana Nadell with an alibi.