A pair of broken rails caused major headaches for straphangers during the evening rush hour Monday.

The MTA said damage at a rail south of 125 Street and at 72 Street on the southbound express track around 4:45 p.m. caused delays and changes for several lines including the A, B, C and D trains.

B trains are running between Brighton Beach and Whitehall St-South Ferry, along the R line between DeKalb Av and Whitehall St-South Ferry in both directions. Southbound A trains are running locally between 145 St to 59 St-Columbus Circle, while D trains run locally between Norwood-205 St and 59 St-Columbus Circle in both directions.

The MTA urged commuters to check mta.info for the latest updates.