BOSTON -- A structural crack in a wall of the Boston's Old South Church was caused by work on a Massachusetts Bay Transportation Authority station below, according to the Associated Press.

Officials found the crack in the church's "fine arts wall," which includes a decades-old stained glass window.

A contractor for the MBTA has been installing elevators at the Copley Square station to make it handicapped accessible, and MBTA officials said that they would hold the contractor responsible, the Associated Press reported.

"The project involves sinking two elevator shafts -- one across the street, one adjacent to the church," said Charles O'Reilly, of the MBTA.

Months ago, MBTA designers worried about possible effects on the church and adjusted the construction plan.

"Our expectation in that change of design was that we were cutting off the possibility of any damage to the church foundation, and unfortunately, as I said, there has been some damage experienced. We don't know yet what caused it," O'Reilly said.

"Our architects will be looking, structural engineers," said the Rev. Nancy Taylor, of the Old South Church. "Our organ builder because our organ is back there -- the major works of the organ. We have the stained-glass window, which is 140 years old, so we are looking at all of that."

The church is at the corner of Dartmouth and Boylston streets in Copley Square. The crack is in the building's foundation on the Dartmouth side and stretches from the roof to the ground.

Uncut: Crack Found In Old South Church | Officials Investigate Structural Crack In Church

A woman who sings at the church said that she spotted the crack earlier this week when she went to rehearsal at the Old South Church, according to a letter to the MBTA that Alecia Batson posted on her blog.

"The crack begins at the foundation, works its way up the right side of the stained glass, (winds) its way around one of the rose windows and then angles toward the ceiling, making its way across the plaster to the lantern at the base of the cupola," Batson posted.

Batson said that she is concerned that if the organ is played inside the church it could cause large pieces of plaster to fall.

The National Historic Landmark building was constructed between 1872 and 1875 for a congregation founded in 1669, according to the church's Web site.

The church played a role in American history through the actions of the Sons of Liberty at the Old South Meeting House, where in 1773 Samuel Adams gave the signal for the "war whoops" that started the Boston Tea Party.