PORTLAND — Five historic buildings and two sites are “in peril” due to deteriorating conditions and a lack of protection, Greater Portland Landmarks said Thursday.

The preservation group issued its inaugural list of threatened structures and landscapes, including The Portland Company complex on Fore Street; the Maine National Guard Armory in South Portland; the Masonic Temple Grand Lodge on Congress Street; the Grand Trunk office building on India Street and the Abyssinian Meeting House on Newbury Street.

The two sites are House Island in Casco Bay and the Eastern Cemetery on Munjoy Hill.

Hilary Bassett, GPL’s executive director, said the sites on the list are “at a tipping point,” either because they are for sale without any preservation covenants or due to deterioration.

Bassett said the organization decided to put out a list of sites meriting concern to highlight their fragile states and focus public attention on the need for preservation.

Currently, House Island and The Portland Company complex are both for sale. Buyers have been interested in the Grand Trunk building, but a sale is complicated by a complex ownership structure, she said.

None of those three buildings have restrictions that would require a new buyer to preserve the structures, Bassett said.

The other sites made the list due to their deteriorating conditions or deferred maintenance, she said. One, the Abyssinian Meeting House, is being preserved, but made the list due to the high cost of the project, Bassett said.