Commuter trains damaged in a crash in Connecticut were being removed Sunday in the first step to making repairs and restoring service, the agency that runs Metro-North said.

Aaron Donovan, spokesman for the Metropolitan Transportation Authority, said the National Transportation Safety Board, which is investigating the crash, gave Metro-North the OK to remove the trains. Hundreds of feet of track need to be repaired, he said.

"We have a lot of work ahead of us, to restore signals and overhead wires," Donovan said.

Later Sunday, the Connecticut Department of Transportation will announce jointly with Metro-North a plan for the rush-hour commute beginning Monday.

Investigators are looking at a broken section of rail to see if it is connected to the derailment and collision outside Bridgeport that left dozens injured. Seventy-two people were sent to the hospital Friday evening after an eastbound train from New York City derailed and was hit by a westbound train. Nine remain hospitalized.

Service has been suspended between South Norwalk and New Haven, which includes stops at 12 stations.

Donovan compared the loss of service to a "very significant storm."

Most recently, the Waterbury branch of Metro-North was down immediately after the massive Feb. 9-10 snowstorm that blanketed the Northeast.

Investigators said Saturday that the crash was not the result of foul play, but a fractured section of rail is being studied to determine if it is connected to the accident. National Transportation Safety Board member Earl Weener said the broken rail is of substantial interest to investigators and a portion of the track will be sent to a lab for analysis.

Weener said it's not clear if the accident caused the fracture or if the rail was broken before the crash. He said he won't speculate on the cause of the derailment and emphasized the investigation was in its early stages. Officials earlier described devastating damage and said it was fortunate no one was killed.

The crash damaged the tracks and threatened to snarl travel in the Northeast Corridor. The crash also caused Amtrak to suspend service between New York and Boston.

NTSB investigators arrived Saturday and are expected to be on site for seven to 10 days. They will look at the brakes and performance of the trains, the condition of the tracks, crew performance and train signal information, among other things.

The MTA operates the Metro-North Railroad, the second-largest commuter railroad in the nation. The Metro-North main lines -- the Hudson, Harlem, and New Haven -- run northward from New York City's Grand Central Terminal into suburban New York and Connecticut.

The last significant train collision involving Metro-North occurred in 1988 when a train engineer was killed in Mount Vernon, N.Y., when one train empty of passengers rear-ended another, railroad officials said.