FUNCHAL, Portugal -- Relatives of some of the 29 German tourists who died in a bus crash in Madeira arrived on the Portuguese island on Friday as investigators pushed on with the task of finding out why the bus veered off the road and plunged down a slope.
German tour operator Trendtours said it had flown in some of the relatives and that it was working with Portuguese authorities to bring the survivors back.
Visiting the island on Friday, Portuguese President Marcelo Rebelo de Sousa praised the emergency services' swift response to Wednesday's accident in the coastal town of Canico.
Medical authorities said eleven people have so far been discharged and that sixteen remained hospitalized, including the Portuguese driver and a guide who were on the bus with 53 tourists on 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.
A German plane was also expected to take home the injured survivors. But teams made of Portuguese and German doctors were gauging when they would be fit to travel, said Miguel Reis, an official with the main clinic hospital in Madeira's capital, Funchal.
German Foreign Minister Heiko Maas announced plans to send the plane during his visit to the island on Thursday, adding that bodies of the deceased would be transported to Germany only once they are properly identified.
"I hope we can do that as soon as possible," Maas told reporters after laying flowers at the site of the crash with his Portuguese counterpart, Augusto Santos Silva.
A German-speaking Presbyterian pastor in Funchal had planned to hold a memorial service on Friday afternoon to honor the victims.
AP reporters Aritz Parra in Madrid and Frank Jordans in Berlin contributed to this report.