FUNCHAL, Portugal (AP) — A German plane is expected to arrive on the Portuguese island of Madeira on Friday to take home survivors from a bus crash that killed 29 German tourists.

Sixteen people remain hospitalized, including a Portuguese driver and a guide who were on the bus with 53 tourists on Wednesday afternoon when it veered off the road and plunged down a slope.

Late Thursday, German Foreign Minister Heiko Maas said a plane and medical crew were being readied to go to the island, which is 580 miles (935 kilometers) east of Morocco in the Atlantic Ocean.

Investigators suspect that a stuck accelerator pedal could have been the cause of the crash that occurred only some 250 meters (820 feet) after the bus had left the hotel where the German guests were staying, Portugal's TVI reported.

The broadcaster, citing anonymous sources from the prosecution-led investigation, said authorities would wait to complete the probe before releasing final conclusions.

Maas said that the bodies of the deceased would be transported to Germany once they are properly identified, a process that has to be done "with the utmost care to avoid any mistakes."

"I hope we can do that as soon as possible," Maas told reporters after visiting the injured in Madeira's capital, Funchal. He also laid flowers at the site of the crash with his Portuguese counterpart, Augusto Santos Silva.

Portugese President Marcelo Rebelo de Sousa was expected to visit the injured and the crash site on Friday.

A German Lutheran Church in Funchal is also holding an afternoon Mass to honor the victims and pray for the recovery of the injured, TVI reported.

AP reporter Aritz Parra contributed from Madrid.