(CNN) -- Two Metro-North passenger trains heading in opposite directions collided during rush hour Friday evening in southwestern Connecticut, damaging both trains and leaving dozens injured, authorities said.
A train heading from New Haven to New York City derailed around 6:10 p.m., hitting the other train in Bridgeport, Connecticut, Metro-North spokeswoman Marjorie Anders said. That caused some cars on the second train, which was destined for New Haven, to likewise leave the tracks.
A passenger in a middle car of the New York-bound train, Chris Martin, said his car went dark after the crash, then someone over the intercom "called all the doctors up front." Officials said injuries were not life-threatening.
He and others aboard his "pretty full train" were evacuated, most of them physically fine if emotionally shaken. But there were also signs of injuries, as Martin said he personally saw eight or nine ambulances and a number of wounded people on stretchers.
Brian Alvarez, who saw the wreckage, described the scene as "pretty graphic."
"I saw this one car and it was completely destroyed and they were pulling people out of the car," Alvarez said. "... They were all bloody."
Bridgeport Mayor Bill Finch later told reporters that, while the crash and damage was significant, he didn't know of any life-threatening injuries.
John Cappiello, a spokesman for Bridgeport Hospital, gave a similar assessment. Two people hurt in the derailment were in serious condition at that hospital, one with a facial injury and another with a leg injury, he said.
St. Vincent's Medical Center, also in Bridgeport, was treating 27 patients from the incident, hospital spokeswoman Lucinda Ames said. One of those was in serious condition, while the rest had minor injuries like "you might get in a car accident."
Power has been shut off along the line and service has been halted -- westbound past Bridgeport, which is about 60 miles northeast of New York City on the Long Island Sound, and eastbound beyond South Norwalk -- because of the derailment.
Amtrak also announced early Friday night that it had suspended all travel between New York and Boston indefinitely after the crash.
Bridgeport's mayor said such travel headaches could persist for weeks, because the two tracks affected by the derailment -- which are both "shot right now" -- may take weeks to repair. Because of a bridge replacement project, those two tracks are the only way in and out of New York City by train from that part of Connecticut.
Workers will need to not only remove disabled trains, but also remove the tracks, regrade the rail bed, then lay down the tracks again, according to Finch.
"This is our pipeline to New York City, and it's going to be shut down for some time," the mayor said. "And it's going to cost this region a great deal of money, frankly, not just to repair it but the lost wages and the lost economy."
CNN's Morgan Winsor and Mayra Cuevas contributed to this report.