A group of alleged Mafia members and associates appeared in court Thursday, a day after they were arrested in sweeping law enforcement raids.

Several of them could face the death penalty if convicted of their crime, including all six who live in Westchester.

Steven Crea, also known as "Wonderboy," is among them. The Crestwood resident is the alleged underboss of the notorious Lucchese family.

Along with his son, who has the same name and lives in New Rochelle, he faces federal murder and racketeering charges.

Investigators spent years performing their probe, creating hundreds of recordings, wiretaps and surveillance videos. The discovery phase is expected to take months to complete before a trial can begin.

The 19 defendants are due back in court Sept. 20.