A North Merrick man accused of plotting to bomb the Nassau County Department of Social Services building last year pleaded guilty to multiple criminal charges in Mineola on Monday, Nassau District Attorney Anne T. Donnelly said.

James Luca also pleaded guilty to detonating an explosive device on his ex-wife’s car and stealing property from a relative by forging loan papers and a deed during a hearing before Nassau County Judge Terence Murphy, Donnelly said in a news release.

At a news conference following Luca’s arraignment in November, Donnelly said the defendant intended to blow up the social services building because he blamed Nassau County Child Protective Services for revoking his visitation rights with his children. Donnelly said at the time that Luca and his ex-wife, the parents of four children, had been engaged in a lengthy divorce.

Luca is a "dangerous and unpredictable" defendant who sowed fear and terror, Donnelly said in Monday’s statement.

Luca, 47, pleaded guilty to two counts of first-degree criminal possession of a weapon, obstruction of governmental duties, residential mortgage fraud and other charges. He is expected to be sentenced to 9 years in prison when he returns to court on July 8.

"James Luca belongs behind bars," Donnelly said.

Donnelly's office charged Luca in November with the crime of terrorism, which comes with a maximum sentence of 25 years to life. The crime of terrorism charge was not included in Monday's plea.

"Today James Luca took responsibility for conduct that occurred at a time of great personal turmoil in his life," said his attorney Brian Griffin, of Garden City. "To be clear, his conduct was wrong, but it certainly was not an act of terrorism for which he was originally charged. We are gratified that these matters have been resolved."

Authorities said Luca and a co-defendant, Jayson Anthony Reyes, also of North Merrick, met up in the early hours of Sept. 17 and drove to the social services building on Charles Lindbergh Boulevard.

While Reyes acted as a lookout, Luca placed a 20-pound propane tank and a 1-pound propane tank at the doors of the building, with a porch on top of the tanks. Surveillance video showed Luca attempting to throw lighted road flares at the homemade explosive, which failed to ignite.

Luca and Reyes left the scene, abandoned their car on Warren Street and entered another car they had left on the street earlier that morning. They then returned to Luca’s home, authorities said. The device was discovered later that day and reported to the police. The Nassau police Arson and Bomb Squad, the Uniondale Fire Department and the Nassau Fire Marshal’s Office evacuated the building and secured the bomb.

Police later discovered another 20-pound propane tank a short distance from the scene, Donnelly said. They also found additional road flares in the abandoned vehicle. Luca and Reyes were arrested on Oct. 3.

Reyes, who worked at Luca’s auto shop, pleaded guilty to first-degree criminal possession of a weapon and other charges. He is scheduled to return to court on July 23, according to court records.

Luca also pleaded guilty to detonating an explosive device on his ex-wife’s car at her home in North Merrick, shattering the windshield in February 2023, according to prosecutors. He also acknowledged damaging her car on another occasion, in January 2024.

Luca also pleaded guilty on Monday to stealing property from a relative through a mortgage fraud and identity theft scheme, Donnelly said. Luca forged loan papers and a deed to change the home’s ownership, and then obtained a $410,000 mortgage on the property. The forged loan and fraudulent mortgage went into foreclosure, leaving the relative with more than $600,000 in debt.

Donnelly said Luca obtained credit cards using the same relative’s personal information, running up more than $200,000 in unpaid charges. He also used another relative’s name to turn on PSEG Long Island service at three properties, including his own residence.