ZURICH • One woman died and two girls were in serious condition a day after an attack on a Swiss train by a man armed with a knife and flammable fluid which also claimed the suspect's life.

The 34-year-old woman and the 27-year-old suspect died from their injuries yesterday, St Gallen cantonal police said. Five people were stabbed or burned during the attack by the Swiss man on a train nearing Salez station in St Gallen in north-east Switzerland on Saturday afternoon.

A sixth person, who was not a passenger but a man on the platform at Salez station, suffered smoke inhalation as he rushed in to pull the attacker - who was on fire - from the train, police said. "His intervention probably prevented worse," police spokesman Hanspeter Kruesi told the Blick daily.

Pictures published by Swiss media yesterday showed burnt-out seats in front of a blackened window, the chairs covered with ash and the upholstery burned to a crisp, while on the platform was a pool of blood.

Police said images of the attack had been caught on surveillance footage, allowing them to determine that the man had acted alone.

The footage, which was not immediately made public, showed the man, who was carrying a knife, pouring out flammable liquid and setting it alight, police said.

The woman who died yesterday morning in the attack had received a large portion of the flammable liquid over her, leading to speculation she might have been the main target of the attack.

Police spokesman Bruno Metzger said a crime of passion was one possibility.

But Mr Kruesi said on Saturday it did not appear that the attack was directed at a single person. He said it remained unclear if the attacker knew any of the victims.

Swiss police said yesterday there was so far no indication that the attack was an act of terror.

"The question of motive remains," police from St Gallen said in a statement, stressing: "To date, there is no indication this was a terrorist or politically motivated act."

While no motives have been ruled out, the police statement should calm some of the speculation circulating since the attack, which followed several months of violent, often deadly assaults in Europe, many of which were claimed by terror group Islamic State in Iraq and Syria.

Police have searched the house of the attacker - who was not of immigrant origin and did not have a criminal record- located in a canton neighbouring St Gallen.

Two men aged 17 and 50, two women aged 17 and 43 and a six-year-old girl had burns and stab wounds, according to police. One of the women and the child were in serious condition. The identities or nationalities of the victims have not been released by the police.

This was the first attack of its kind in Switzerland in recent memory. In December last year, a 33- year-old Swiss man broke into his neighbours' house in Rupperswil and killed four people before setting the house on fire, in an incident that shocked the country.

REUTERS, AGENCE FRANCE-PRESSE