Police stand outside an Islamic center in central Zurich, Switzerland December 19, 2016. [Photo/Agencies]

ZURICH - A man stormed into a Zurich mosque on Monday evening and opened fire on people praying, injuring three, Swiss police said.

They said they had collected evidence inside the building and would make more details available on Tuesday. They declined to comment on the potential motive.

Two of the three men -- aged 30, 35 and 56 -- were seriously injured in the attack shortly after 5:30 pm local time (1630 GMT) near the main train station in Switzerland's financial capital, Zurich police said.

A third sustained less severe injuries. All three were brought to hospital.

The unidentified suspect, a man around 30 years old who according to witnesses was wearing dark clothing and a dark wool cap, fled the mosque, police said.

Police said a body was found nearby but would not comment on any link to the shootings while investigations continued.