Swiss aviation officials lifted a nighttime flight ban at Kloten airport to allow the Qatari royal planes to land.
The Qatari royal family issued a statement saying that 64-year-old Hamad Bin Khalifa al-Thani had broken his leg while on holiday, AFP reported.
The former emir is currently in Zurich for physiotherapy following an operation, the statement added.
Earlier a spokesman for Switzerland's Federal Office of Civil Aviation confirmed local media reports that multiple aircraft made unscheduled landings at Zurich-Kloten airport overnight from December 25th to 26th and that the planes were part of the Qatari royal fleet.
"The emergency landing clearance was given by the Swiss air force," he told AFP, explaining that the civil aviation office was closed during the hours in question.
Night landings and takeoffs are typically forbidden at Zurich-Kloten to avoid disturbing local residents.
Swiss foreign ministry spokesman Georg Farago told AFP in an email that the federation was informed about the "stay of members of Qatar's royal family in Switzerland" without giving further details.
According to Zurich's Tages-Anzeiger newspaper, the first Qatari plane, an Airbus, landed in Zurich from Marrakesh shortly after midnight on December 26th.
Members of the Qatari royal family had reportedly been on holiday at a Moroccan resort in the Atlas mountains.
A second flight landed at Zurich-Kloten at 5am on December 26th, with a third plane coming 15 minutes later, both having originated in Doha, the paper reported.
According to the Tages-Anzeiger, six more planes linked to the Qatari royal family and government landed in Zurich through the weekend.
It is not clear whether the airforce knew that the medical emergency was a broken leg, the 20 Minuten website reported.
"We decide on a case-by-case basis whether to grant permission for an exceptional landing," the paper quoted airforce spokeswoman Delphine Allemand as saying.
"The plane was already in the air when we received a landing request," Allemand said.
Social Democrat parliamentarian Thomas Hardegger, who is chairman of an association representing residents affected by noise in the area of the airport called the decision a "scandal".
But a parliamentarian for the right-wing People's Party, Alfred Heer, played down the incident saying it was not every day that the night flight ban was lifted, 20 Minuten reported.