On Dec. 22, New York city bus drivers report for work at the Michael J. Quill bus depot on Manhattan's west side after a three day transit strike. (Source: CRIENGLISH.com/AP)

Faced with mounting fines and the rising wrath of millions of commuters, the city transit union sent its members back to work without a new contract Thursday and ended a crippling, three-day strike that brought subways and buses to a standstill.

Union members were told to return to their jobs starting with the evening shift. Buses were expected to be rolling again by evening. And most subways were expected to be running by the Friday morning rush, just two days before Christmas.

"I'm ecstatic that it's over, but I'm still really mad that they did it," said Jessica Cunningham, 21, who was in town for the holiday. "I really think it's screwed up that they decided to strike the week before Christmas."

The breakthrough came after an all-night session with a mediator. Around midday, leaders of the 33,000-member Transport Workers Union overwhelmingly voted to return to work and resume negotiations with the transit authority on a new three-year contract.

"We thank our riders for their patience and forbearance," said union local president Roger Toussaint.

While the deal put the nation's largest mass transit system back in operation, it did not resolve the underlying dispute—pension contributions were the main sticking point—meaning there could be another walkout if the negotiations fail.

The strike cost the city untold millions in police overtime and lost business and productivity at the very height of the Christmas rush and forced millions of commuters, holiday shoppers and tourists to carpool, take taxis, ride bicycles or trudge through the freezing cold. But the strike did not cause the utter chaos that many had feared, and traffic in many parts of town was surprisingly light.

"In the end, cooler heads prevailed," Mayor Michael Bloomberg said. "We passed the test with flying colors. We did what we had to do to keep the city running, and running safely."

The walkout, which began early Tuesday, was New York's first citywide transit strike in more than 25 years. The workers left their jobs in violation of a state law prohibiting public employees from striking.

The return to work was announced just minutes before Toussaint and two of his top deputies were due in a Brooklyn courtroom to answer criminal contempt charges that could have landed them in jail.

Earlier this week, state Justice Theodore Jones fined the union $1 million a day for striking. And under the state no-strike law, the rank-and-file members were automatically docked two days' pay for each day they stayed off the job.

"I'm ready to work the rush hour this afternoon if they let me," bus driver Ralph Torres said from the picket line as the breakthrough was announced.

The strike left bitter feelings across the city.

"I think it was all for nothing," said commuter Lauren Caramico, 22, of Brooklyn. "Now the poor people of the TWU are out six days' pay, and nothing gained."

Gov. George Pataki warned there was no possibility of amnesty for the striking workers who were penalized financially. The fines "cannot be waived. They're not going to be waived," he said.

Just before the deal was announced, an off-duty firefighter was critically injured when he was struck by a private bus while riding his bicycle to work. It was the first serious strike-related injury.

A chief sticking point in the talks was a Metropolitan Transportation Authority proposal to require new hires to contribute 6 percent to their pensions, up from the current 2 percent for all employees. The pension proposal remained on the table despite the end of the walkout.

The vote to return to work was blasted by TWU dissidents who felt the union had caved in.

"This was a disgrace," said TWU vice president John Mooney. "No details were provided to the executive board. (Toussaint) wants us to discuss the details after Christmas."

After workers returned to the job, the judge overseeing the dispute adjourned all further action in the case until Jan. 20.

"I'm pleased on behalf of the people of the city of New York," Jones said. "Hopefully, we'll be able to salvage Christmas."