Updated

The U.S. Attorney's Office says four men have been arrested in connection with the theft of a $2 million ruby during a jewelry store heist in Wilmington, Del.

Spokeswoman Kimberlynn Reeves said an indictment that had been returned in December against the suspects was unsealed Thursday after their arrest.

The four are accused of robbing Stuart Kingston Jewelers in November 2011 and escaping with $4.4 million in jewelry, including the 5-inch, 4-pound Liberty Bell Ruby, made from the largest mined ruby in the world.

The indictment says the armed, masked men restrained store employees with zip ties and duct tape and smashed glass display cases with hammers.

Reeves said none of the jewelry has been recovered.