The Long Island Rail Road shut down at 12:01 a.m. Saturday after a group of unions failed to reach a new contract deal with the MTA and went on strike, according to officials on both sides of the negotiations.

The move brought service on the country’s busiest commuter rail service to a halt for the first time in over 30 years.

The MTA and five unions representing a majority of the LIRR’s workforce couldn’t come to an agreement over pay raises and changes to work rules before a midnight strike deadline. As long as the strike drags on, some 275,000 daily commuters who use the railroad will need to find other ways to travel.

If the strike continues into Monday, the MTA plans to deploy limited shuttle bus service for commuters to connect to the city’s subway stations. Officials estimated the alternative service would cost as much as $550,000 daily.

At the Bay Shore, Hicksville and Mineola LIRR stations, shuttles will take commuters to the Howard Beach-JFK A train station.

At the Huntington and Ronkonkoma LIRR stations, shuttles will take commuters to the Jamaica-179th St. F train station.

Commuters in Nassau County can also use NICE bus services to get to the Flushing-Main St. station to ride the 7 train or the Jamaica Bus Terminal in Queens, which is close to the 169th St. F subway station.

A representative of the New York State Department of Transportation said it was preparing mitigation measures in anticipation of busier roads on Long Island, including electronic message signs on the highways warning drivers to plan ahead. State transportation officials also deployed more tow trucks, highway maintenance staff and traffic signal technicians in case of an emergency along the roads.

“We have to recognize over 277,000 daily customers. We couldn’t possibly accommodate that by buses. We have to do everything we can,” LIRR President Rob Free said last month while going over plans to provide shuttle buses if the workers walked off the job.

The MTA and Gov. Kathy Hochul are also encouraging businesses and their employees to work from home if possible.

It’s unclear how long the strike will last, but commuters will feel the pain if it persists through the start of the work week on Monday. An NJ Transit strike last year lasted three days. The last LIRR strike in 1994 lasted two days.

In the lead-up to the strike, MTA officials said they were in agreement with the unions on pay bumps for the first three years of a four-year contract, but there was a stalemate on pay for the final year.

At an MTA board meeting in April, agency officials said the MTA would likely have to hike fares by 8% and cut jobs to avoid a deficit if it gave the union the pay bump it was asking for.

“Obviously, this is not the result we were looking for,” MTA Chair Janno Lieber wrote in a statement. “But I, and this MTA Board, have been clear that we cannot responsibly make a deal that implodes MTA’s budget.”

“We refuse to make a deal that puts it on riders and taxpayers to fund outsized wage increases – far beyond what anyone else at the MTA is getting – and for folks who are already the highest-paid railroad workers in the country,” Lieber added.