VIENNA, Dec. 22 (Xinhua) -- At least 12 people were injured, four of them seriously, as two passenger trains collided near the Austrian capital of Vienna, local media reported on Friday.

The two regional trains were in a relatively low speed when what appeared to be a side-on collision occurred at about 6 p.m. local time (1700 GMT) near the station in Kritzendorf, some 19 km north of Vienna.

Two carriages from one of the trains derailed and turned over. The passengers were left locked in the carriages as rescuers rushed to the scene to help them out.

Details of the incident were emerging slowly and authorities said four people were severely injured while another eight were slightly hurt. They were given immediate medical attention.

A rail spokesperson said the clean-up effort would take place as soon as possible. An investigation into the crash was also underway.