BERLIN (AP) — Swiss police say a 34-year-old woman has died from wounds suffered after a man attacked her and others with a knife and a burning liquid aboard a train.

St. Gallen canton (state) police said the woman died Sunday morning of wounds suffered in the Saturday afternoon attack on a Swiss train.

Four others — including the suspect — remain in critical condition; a total of seven were wounded.

Police spokesman Hans-Peter Kruesi told The Associated Press authorities have not been able to interrogate the 27-year-old suspect, a Swiss man from a neighboring canton, due to his condition.

Kruesi said so far police have found no indications the man had ties to extremist groups.

The attack occurred as the train neared the station in Salez, close to the Liechtenstein border.