Operations are gradually returning to normal, but some flights were still delayed at John F. Kennedy International Airport in New York City on Monday after a water pipe break caused 352 delays and 46 cancellations the previous day.

The incident compounded problems resulting from a winter storm that hit New York City on Thursday, causing delays and cancellations.

The pipe break sent about 3 inches of water into the privately operated Terminal 4. Streams of water cascaded from a ceiling, requiring people to slog through pools of water. Power to the affected areas was temporarily shut off for safety reasons and additional staff and buses were arranged to assist travelers. Domestic arrivals and departures were delayed and some international flights were diverted or cancelled.

The Port Authority of New York and New Jersey issued an apology to travelers, and said that it would investigate the breaking of the water pipe, which feeds a sprinkler system, and hold all responsible parties accountable.

“What happened at JFK airport in unacceptable, and travelers expect and deserve better,” said Rick Cotton, executive director of the port authority, in a statement. “While the water pipe break that occurred appears to be weather-related, we have launched an investigation into the incident to determine exactly what occurred and why an internal pipe was not weather protected, and whether any other failures contributed to this disruption.”

Cotton emphasized that the terminal that was flooded is operated by a private company, not the Port Authority. Although the Port Authority is the landlord and overall operator of the airport, the airlines and other private companies operate the six terminals and are responsible for getting planes to and from gates, and getting passengers and their baggage on and off planes.

The pipe break was preceded by several earlier problems. In the aftermath of Thursday’s storm, operations slowed due to frozen equipment and understaffed crews. Cotton contends that given the situation, airlines shouldn’t have continued bringing so many planes to the airport.

“What broke down—and it broke down badly—was the coordination between terminal operators and the airlines to assure that there were gates available for the arriving airplanes,” Cotton said at a press conference.

On Saturday night, international flights at Terminal 1 and Terminal 2 were nearly paralyzed.  International flights bound for Terminal 1 were blocked from arriving and reportedly, some passengers in Terminal 4 were so aggravated over a flight being cancelled that fights broke out.