An immigrant training center in Helsinki was evacuated due to toxic gas on Thursday, local media reported.

So far, 11 people reportedly have symptoms of breath difficulty and five have been sent to hospital, said the reports.

The incident occurred shortly before Thursday noon in the Axxell Multicultural Center, which is about 3 km north of the city center of the Finnish capital.

The rescue department told media that the symptoms were caused by an unidentified gas inside the training facility, which offers teaching and testing for immigrants.

Police speculated that the case of toxic exposure was possibly a result of a deliberate action.

Petri Korhonen, the fire chief, said that the irritant gas did not come from inside of the building, but from an external source.​