Four Germans were among the seven people who died in the collision of a helicopter and an ultralight plane on the Spanish island of Mallorca on Sunday, the German foreign office confirmed early Monday.

The foreign office declined to disclose details. The Germans who were killed were identified in media reports as a family from Munich. The German tabloid Bild spoke of a couple and their two children aged 9 and 11.

The helicopter pilot was reportedly Italian. The two people on the light plane were described as a man from Valencia and his male friend, Spanish broadcaster RTVE reported.

 What caused the accident, which happened in the early afternoon near the town of Inca, was not known.

Both the ultralight aicraft and the helicopter burst into flames. No-one survived the accident.

‘We are concerned and horrified by the accident,’ Francina Armengol, the president of the Balearic Islands, tweeted earlier. ‘Our thoughts are with the victims.’  Spanish Prime Minister Pedro Sanchez also sent his condolences for the victims' families.

 Local people rushed to the crash site after hearing a loud bang.

 Police and fire services were called to the scene, as the plane went up in flames, reports said.

 Parts of the helicopter were strewn across an old country road, and the plane had crashed onto the grounds of a country estate, Sebastia Oriol, head of security for the municipality of Incam, told local broadcaster IB3.

The company that runs the helicopter tours for tourists, Rotorflug Helicopters, confirmed the crash.

‘The cause of the accident is still completely unclear,’ the company, which is based near Frankfurt in Germany, said in a press statement.

 ‘The German Federal Aviation office (LBA) and the German Federal Bureau of Aircraft Accident Investigation have already been informed by Rotorflug,’ the statement continued.

Authorities have launched an investigation into the cause of the accident.