ROL: The latest mortar rounds exchanged by two rival factions of Satmar Hasidim involve a huge synagogue under construction in the Williamsburg section of Brooklyn, where their movement is based.

The side that dominates in Kiryas Joel complains that its enemies in Brooklyn have built “partitions, walls, roof enclosures and other improvements” in recent weeks, even though ownership of that and other Satmar property is still in dispute in court.

That faction filed a class-action lawsuit in Orange County last week on behalf of 5,000 member, demanding that work cease until an appeals court rules on the ownership. Those members are said to have spent a total of $10 million – as much as $20,000 apiece – for seats in the future shul.

Litigation has raged for five years between supporters of Zalmen and Aron Teitelbaum, brothers vying to lead the Satmar movement. Each brother claims to lead 120,000 Satmar members worldwide since the death of their father, Moses, the prior grand rebbe, on April 24.

In this latest round, state Supreme Court Justice Joseph Owen issued a temporary restraining order on Monday to halt construction. But the appeals court in Brooklyn overturned that ruling yesterday after Zalmen’s side objected.

Afterward, Scott Mollen, a Manhattan attorney representing the Zalmen faction, called the latest suit an attempt to circumvent the appeals court.

“I have never seen litigation where there have been more improper acts than in this case,” Mollen said.

He said his clients merely put up a roof to protect the synagogue interior and did temporary work to allow observances. They don’t plan to continue construction until the ownership question is decided, he said.

“We don’t care about maintaining or using it,” replied Richard Mahon, a Newburgh attorney for the Aron faction. “But we don’t want any construction to take place until the appeals court decides.”