ROME — Italy cut in half the number of aircraft that could be handled in its airspace Friday after overnight problems hit the data transmission network supporting air traffic control services nationwide, air navigation company ENAV said. It ruled out a cyberattack.

ENAV said it was using alternative data transmission systems to allow as many departures as possible Friday morning, including intercontinental flights, while operating at 50% of overall air traffic capacity.

The company said contingency systems had allowed air traffic to operate normally until 6 a.m. But as traffic increased and the problems persisted, it introduced measures to regulate flight flows and reduce the number of aircraft that could be handled in Italian airspace.

The disruption caused delays at airports across the country, including Rome’s Fiumicino airport and airports serving Milan and Bergamo.

ENAV said technicians had traced the anomalies to the data transmission network and were deploying all available resources to restore full operations and minimize disruption.

It ruled out malicious activity and said flight operations remained safe.