GENEVA, Aug. 13 (Xinhua) -- A man on Saturday set fire to flammable liquid on a train travelling between Buchs and Sennwald in Switzerland, injuring seven people including the man himself, the Switzerland's St. Gallen cantonal police reported.

According to the Swiss authorities, the attacker was a 27-year-old Swiss male who was wielding at least one knife. Among the wounded there were a six-year-old child, three women and two men.

Passengers were either injured by flames or by stabbing, the authorities said.Rescue teams on site have transferred those affected to various hospitals.

Damage to the train, which was nearing Salez station when the attack took place at around 2:20 p.m. local time, amounted to around 100,000 CHF (103,000 U.S. dollars).

The attacker's motive remains unclear. A criminal investigation has been kicked off.

The latest development came after a spate of attacks across Europe, notably in France, Belgium and Germany.

In May, a man stabbed four people at a train station on early morning in Grafing near Munich. One man later died.

On June 23, a masked gunman stormed a cinema in western Germany and took some people hostage. He was shot dead by police. No one was injured.

Last month, a 17-year-old Afghan asylum-seeker attacked passengers with an axe on a train near Wuerzburg in Germany, wounding five people before being shot dead by police, while a 27-year-old Syrian killed himself in a suicide bomb attack, injuring 15 people in Ansbach.

In response to the recent attacks, German Interior Minister Thomas De Maiziere has introduced several measures to increase security in Germany.

In France, Mohamen Lahouaiej Bouhlel, a 31-year-old Tunisian national, drove a white truck at high speed into crowds gathered along the promenade in Nice to watch fireworks marking the French national day on July 14, killing 85 people.

Belgium's capital Brussels was also struck in March this year by twin bombings targeting at the city's airport and metro.

Saturday's attack was the first of its kind in Switzerland, but local police source has declined to confirm any terrorism links to the attack, saying that the investigation is still underway.