In a statement, the Südostbahn (SOB), which operated the train in question, said it would reconsider its security measures following the attack which killed two, including the assailant himself, and left five others injured.
Chairman Hans Altherr said the company was “deeply affected” by the tragedy.
“We send our deepest condolences to the families of the victims and wish the injured a quick recovery,” he said.
“After such an extreme event, the SOB will reconsider its security arrangements, since the safety of passengers is our first priority,” added the statement.
But could increased security have prevented such an attack?
Martin Graf, head of public transport security agency Securitrans, feels not. In an interview with Tages Anzeiger he said security services had “no chance” of being in the right place at the right time to prevent a surprise criminal attack by someone who is not on the radar of the authorities.
The region where Saturday's attack happened, at Salez in eastern Switzerland, is a peaceful area and there was “no reason” for security officers to be present in such a place, he said.
Security personnel operate in at peak times in the busiest stations. Staff are sent to a smaller station if information of a potential incident is received, but the fact remains there was no reason for an increased security presence at Salez at that time, he said.
However tighter security measures could perhaps have a deterrent effect, say commentators.
Speaking to the media on Sunday, Hans-Ruedi Schurch, president of LPV, a union for train employees, said every train should have a security officer on board, a measure abolished for regional trains 20 years ago.
“Back then the feeling of safety in the trains was better than it is now,” he said.
“Though an unarmed security officer may not be able to stop an attack like the one this weekend, it could perhaps dissuade certain people from such an act,” he said.
Others called for more surveillance in train stations.
“An stronger presence in stations would help dissuade potential assailants and intensify security checks on people and luggage,” said Kurt Schreiber of Pro Bahn, reported 20 Minutes.
Swiss federal railways (SBB), meanwhile, said it would wait for the outcome of the investigation before assessing whether it should implement any additional security measures.
According to the latest information, a six-year-old girl and 43-year-old woman injured in the attack are now out of danger.
However a 17-year-old girl remains in a serious condition.