Seven people were killed when a helicopter on a sightseeing tour and a small plane collided mid-air over the island of Mallorca, Spanish authorities say.

The victims included three adults and two children on the helicopter and two local men in the plane, according to the regional government of Spain’s Balearic islands, which include Mallorca.

Four Germans were among the seven people who died in the collision.

The German foreign office confirmed the deaths early on Monday, but declined to disclose details of the incident.

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, while Spanish broadcaster RTVE described the two people on the light plane as a man from Valencia and his male friend.

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 on to the grounds of a country estate, Sebastia Oriol, head of security for the municipality of Incam, told local broadcaster IB3.

It was also not known what caused the accident, which reportedly happened in the early afternoon on Sunday near the town of Inca.

“We are concerned and horrified by the accident,” Francina Armengol, the president of the Balearic Islands, wrote on Twitter. “Our thoughts are with the victims.”

Spain’s caretaker prime minister, Pedro Sanchez, sent his condolences to the victims’ families on Twitter and expressed sadness at the “tragic accident”.

-AAP