PARIS (AP) — Trains were running again Wednesday in both directions through the Channel Tunnel between continental Europe and the United Kingdom but problems remained after a day of travel chaos caused by power malfunctions.

The tunnel operator, Eurotunnel, said the 50-kilometer (32-mile) undersea link was back to “full capacity” after a power fault inside it was fixed overnight Tuesday. The short statement didn’t detail the cause of the power failure.

But Eurostar, which runs passenger trains through the tunnel, warned of continued possible delays and cancellations because of “knock-on impacts” from the severe disruptions on Tuesday. Its website showed delays Wednesday to London-Paris, London-Brussels and London-Amsterdam trains in both directions and early morning cancellations.

Tuesday’s hours-long interruption of cross-Channel train services and a resulting cascade of cancellations upended travelers’ end-of-year getaway plans and provoked scrambles for flights and buses.

Another power malfunction Tuesday on the U.K. side that Eurostar said was related to the electrical fault inside the tunnel also caused severe delays for passengers aboard three trains, Eurostar said.

It said an overhead power cable fell onto a Eurostar train from London to Paris, near the tunnel entrance, and that an effort to move the train with its passengers inside proved “very complex.” The power failure also caused severe delays to two trains to Brussels, Eurostar said.

Passenger Ghislain Planque told French broadcaster BFMTV that his Eurostar journey Tuesday evening from London to France was meant to take just under 90 minutes but instead took around 11 hours, with passengers stuck overnight in the train that had only intermittent power.

“We were left without electricity, so with no heating, no air-conditioning, no possibility to charge phones,” he said. “We were in total darkness for some of the time.”