A man prosecutors called a "killing machine" when he was on trial for six murders was sentenced Friday to life behind bars by a judge who said he could not recall "immorality in such epic proportions."

Justice Daniel FitzGerald sentenced Fausto Gonzalez, 37, who was convicted earlier this month in Manhattan's state Supreme Court of killing six men in the 1990s. Prosecutors say he killed one man just so he could steal his motorcycle and then drove over the victim as he sped away.

Assistant District Attorney Robert Walker said before the sentencing that Gonzalez was a "remorseless," "merciless" and "unrepentant" assassin who killed for revenge, killed for money, and sometimes "for no reason at all."

John Akdikmen, a retired police detective sergeant and friend of victim Alexander Pierce, the owner of the motorcycle, told the court Gonzalez was "a coward and a lowlife" who killed "a good and decent man who never hurt anyone."

Carolyn Recchio, one of the jurors who convicted Gonzalez, said she felt justice has been served. "I feel very happy to have been a part of this," she said.

Recchio, a marketing specialist at Citigroup, said that when some of the victims' families read statements expressing closure, she felt it too.

Gonzalez's lawyer, Sol Schwartzberg, had told jurors that some of the prosecution's "cooperators" were arrested in another investigation and had lied to police and prosecutors about Gonzalez to get reduced sentences.

Schwartzberg asked the judge to make his client's sentences concurrent — to be served at the same time — although there was no practical effect in doing that.

FitzGerald refused, saying, "I have a hard time recalling any case involving immorality in such epic proportions. I saw not a twinge of regret or any decent human emotion during the trial."

A separate sentence for each victim is acknowledgment of the death and value of each, "something that never crossed your mind," the judge told Gonzalez.

FitzGerald sentenced Gonzalez to two prison terms of life without parole and four terms of 25 years to life. The judge said the sentences were to be served consecutively to each other and to the life sentence Gonzalez is already serving for a murder in Connecticut.