[Batpuff]

BOSTON, Massachusetts (AP) -- Falling concrete slabs crushed a car inside one of the city's troubled Big Dig tunnels, killing a woman and tying up traffic Tuesday with another shutdown in the massive building project that has become a central route through the city.

The car's driver was able to crawl through a window to escape, but his passenger was killed when the massive, 3-ton concrete panels fell, authorities said.

Inside the Interstate 90 connector tunnel, beneath an industrial area of South Boston, concrete slabs could be seen against the tunnel wall and across the roadway. (Watch what led to the woman's crushing death -- 1:25)

Massachusetts Turnpike Authority Chairman Matthew Amorello said Tuesday he doesn't believe safety is compromised elsewhere in the tunnel system, but the damaged section was closed indefinitely for repairs and inspections.

The ceiling panels fell because a steel tieback, holding a 40-foot ceiling section in place, gave way, Amorello said.

"There was a snapping sound heard," Amorello said. "One of the tile panels from the roof released. It caused a series of panels to be released."

Amorello said he was confident that section, about 200 feet in all, was the only area of the Big Dig where that type of tieback was used. The ceiling panels were erected in 1999 and the tiebacks were bolted to a concrete ceiling.

"Any responsible party will be held accountable for what happened," Amorello said. "This is an unacceptable, horrible tragedy."

He said the contractor was Modern Continental. There was no answer early Tuesday at the company's office.

The $14 billion Big Dig highway project, which buried Interstate 93 beneath downtown and extended the Massachusetts Turnpike to Logan Airport, has been criticized for construction problems and cost overruns. There have been water leaks and at least one incident when dirt and debris from an airshaft fell onto cars.

In May, prosecutors charged six current and former employees of a concrete supplier with fraud for allegedly concealing that some concrete delivered to the Big Dig was not freshly mixed.

Amorello said preliminary investigation shows that the quality of the concrete was not to blame for the fatal accident Monday night. The ceiling collapse happened about 200 feet from the end of the connector tunnel, near the entrance to the Ted Williams Tunnel, which goes under Boston Harbor to the airport.

Tuesday morning, the shutdown backed up traffic for miles as commuters tried to navigate the detours. Officials urged drivers, particularly those headed to Logan airport, to use public transit instead.

The victims were identified by State Police Tuesday as Milena Delvalle, 38, and Angel Delvalle, 46. Delvalle was treated for minor injuries.

"The driver's side stayed more intact than the passenger's side," State Police Maj. Michael Mucci said. "He was able to crawl out the window. There was only about 6 to 12 inches. But he was able to get through."

[15thRegionCrazy]

That's horrible news

[crazytaxidriver]

i've been through this tunnel many many times.. and my parents actually went throught it the day before it happend.. horrible..