Twenty one years after he vanished from a Manhattan street, NY1 has learned investigators are looking for DNA evidence to try to solve the disappearance of Etan Patz.

Investigators removed a large amount of ash Thursday night from a defunct coal burning furnace in an East Village apartment burning. The building used to be the home of Jose Ramos, who has long been suspected in the six-year-old Patz's disappearance.

Police believe that Ramos burned Patz's body in the boiler room. The ashes have been taken for testing to see if it matches the boy's DNA or his clothing.

Ramos is now in jail on a child sex charge from Pennsylvania.

Patz disappeared from a SoHo street in May of 1979 as he walked from his Prince Street loft to the bus stop for the first time.