Financial details of the deal were not released, but according to local published reports, the group had originally offered $125 million. The transaction is expected to close this calendar year.

Last month, Miami-based Lennar Corp. was on board to pay a reported $125 million for the site, which is considered to be the heart of South Boston's waterfront. But the firm reportedly missed its down payment for the property opening the door for Stephen Karp, chairman of New England Development, and his group. Calls to the Lennar Corp. were not returned by deadline.

Nicholas Pritzker, the Chicago-based head of Hyatt, spent nearly three years getting the $1.2-billion hotel, office and residential complex permitted, but never managed to secure the necessary financing to move the project forward. Fan Pier is the largest development on the South Boston waterfront and its huge expanse currently sits nearly vacant. It is used largely for parking.