(AP) -- A Rockland County building owner, her son and three others were arrested Thursday on manslaughter, negligent homicide and other charges in connection with a gas explosion last year that killed two people and leveled three Manhattan buildings.

A restaurant worker and a diner in the sushi restaurant on the ground level of one of the collapsed buildings were killed in the explosion. Their badly burned bodies were discovered by rescue workers digging through the rubble days after the blast.

The buildings' owner, Maria Hrynenko, of Palisades; her son, Michael Hrynenko; master plumber Andrew Trombettas; general contractor Dilber Kukic; and worker Athanasios Ioannidis recklessly engineered an illegal gas delivery system that ultimately caused the March explosion and subsequent fire in the trendy East Village neighborhood, authorities said.

"Development, construction and renovation is happening across the city at breakneck speed," said Manhattan District Attorney Cyrus R. Vance Jr., noting that the temptation for taking "shortcuts has never been greater."

Among the shortcuts taken in this case include Trombettas' willingness to rent out his master plumbing license to Ioannidis, a worker who wasn't certified to perform the work, said Mark Peters, commissioner of the Department of Investigation. One time Trombettas was in Greece when he said he'd supervised work, Peters said.

Worker Moises Ismael Locon Yac and diner Nicholas Figueroa died in the blast. "Sopranos" actress Drea de Matteo's apartment was among those destroyed in the explosion.

Eight months before the explosion, Ioannidis used yellow flexible hosing to provide gas into the building from the restaurant's gas meter -- an unsafe hookup that prompted Consolidated Edison utility inspectors to turn off the gas, officials said.

As a workaround, the workers then installed a complex series of pipes and valves to provide a makeshift gas delivery system into one of the buildings via an uncapped gas meter in a locked room in the basement of the adjacent building, officials said.

Shortly before the explosion, and after a restaurant worker called Maria Hrynenko about smelling gas, surveillance video shows Kukic and her son entering and then running out of the basement without warning anyone, they said.

An attorney for Maria Hrynenko didn't return a message seeking comment. Attempts to reach the others were unsuccessful. The defendants were to be arraigned Thursday afternoon, and it wasn't immediately clear if they had attorneys who could comment on the charges.

Two years ago, a gas explosion in an East Harlem building killed eight people and injured about 50. A gas leak was reported before that blast.