Thomas Chiusano was being held early Saturday on $160,000 bond or $80,000 cash bail.
Suffolk County Police Lt. John O'Brien says an East Patchogue woman was mowing her lawn when the 29-year-old Chiusano abruptly dropped off his 5-year-old son and 4-year-old daughter Thursday afternoon.
Police say the woman tried to grab Chiusano's car keys, but he pulled her hair, scratched her and drove off. She called police, who stopped him in nearby Bohemia.
Chiusano is being represented by the Legal Aid Society, which has a policy of not commenting on pending cases. He lives in Brentwood.