A cooperating witness testified Wednesday that he crashed a heavy plumber's wrench into the skull and face of a Florida millionaire's mother in an attack planned by the millionaire's wife and her brother.

And after he was congratulated on "a good job" in the fatal attack, he was recruited into another plot to attack the millionaire himself, hotel heir Ben Novack Jr., the witness said.

Alejandro Garcia, 34, a Nicaraguan illegally in the U.S., testified at the federal murder trial of Philadelphian Cristobal Veliz, 58, and Narcy Novack, 55, of Fort Lauderdale.

They are accused of hiring Garcia and others to kill Ben Novack and his mother in 2009 so that the $10 million Novack estate would fall to Narcy Novack. Ben Novack's father built the Fontainebleau Hotel in Miami Beach.

If convicted of murder in aid of racketeering, the defendants would be sent to prison for life.

Garcia, wearing an orange jailhouse jumpsuit and dark glasses hiding an old eye injury, testified that in both cases, his orders were to "beat up" the victims, not kill them.

But Bernice Novack died shortly after Garcia's assault in April 2009, and Ben Novack was beaten to death three months later in a New York hotel room.

Garcia is expected to testify in detail Thursday about the New York killing. He has already pleaded guilty in the case.