A family of four are dead and a teenage boy is fighting for life in hospital after appearing to jump from their apartment building in the Swiss resort of Montreux on Lake Geneva, police said.

The French family were found at the bottom of a seven storey building in Montreux on Thursday and are believed to have jumped moments after police officers tried to execute an arrest warrant in connection with the home-schooling of a child.       

The four victims, identified as a 40-year-old man, his 41-year-old wife, her twin sister and the couple's eight-year-old daughter, died at the scene, police said. 

The couple's 15-year-old son was seriously injured and has been hospitalised.

Alexandre Bisenz, a police spokesperson, told the 20 Minutes newspaper the family of five appeared to have jumped from their apartment, near the town's lakeside casino. 

A witness at the scene said saw them lying on the ground without shoes before calling the police.  

Police said the incident occurred after two officers arrived at the building, across from Montreux's famous Casino, to execute a warrant for the father in connection with the home-schooling of one of the couple's children on Thursday.

The officers knocked on the door and heard a voice ask who they were.

But when they answered, the apartment went quiet.

After failing to make contact, the officers left, but 'in the meantime, a witness called the police to say that people had fallen from an apartment balcony,' police said.

'We do not know yet whether they fell or if this drama was due to other circumstances,' police spokesman Jean-Christophe Sauterel told the RTS public broadcaster.

While an investigation into the tragedy is ongoing, police have concluded no one else was in the apartment at the time.   

The Vaud cantonal police said in a tweet earlier on Thursday morning: 'Five people were found at the foot of a building.

One of the five victims has been hospitalised and is in serious condition. The four others are dead.' 

Forensic teams are now taking samples from the balcony of the seventh-floor apartment. 

Neighbours said the family was quiet and kept to themselves. 

'We heard nothing from their home, the father never said hello in the hallway and ordered many packages almost daily,' neighbour Claude Rouiller told Swiss newspaper.   

Rouiller said there had been the strong smell of incense coming from the family's apartment in the days leading up to the tragedy, while other neighbours claimed the family were part of a cult. For more in regards to บาคาร่าออนไลน์ take a look at our webpage.   

Another resident, who lives on the first floor of the apartment building, described hearing a 'thud' at around 7am on Thursday morning. 

The neighbour, who wished to remain anonymous, said he went outside to investigate and saw five bodies. 

'I thought it was a bad film - I couldn't fix the image for more than a few seconds,' he said.     

The five people 'would have visibly thrown themselves into the void from the apartment,' Bisenz told news agency Keystone-ATS, adding that the police were alerted to the incident by passersby. 

Bisenz said that an investigation is underway and the five people were found at about 7 a.m.

Thursday outside a building near the city's famed Casino Barriere. He declined to provide further details. 

Around 30 police officers are at the scene and white forensic tents have been set up in front of the apartment building.   

Montreux, a bucolic lakeside city, is best known as a tourist hot spot and in particular for its annual jazz festival.

Bisenz declined to indicate if the victims were Swiss nationals or foreigners.