A man opened fire on or near a bus carrying U.S. soldiers at Germany's Frankfurt airport Wednesday afternoon, killing two people and injuring two others, police said.

A member of Frankfurt Airport security walks past the scene an incident next to an U.S. Army bus in front of the airport in Frankfurt March 2, 2011. (Xinhua/AFP Photo)

Police said the bus driver and one passenger were killed at the scene, while another two were injured -- one in the head and the other in the chest.

It is widely reported by local media that the killed was a U.S. military personnel, but the identity has not been confirmed by the police and the U.S. European Command, headquartered in Stuttgart in southwest Germany.

Police said a 21-year-old suspect from Kosovo had been arrested. There were no details on how many passengers were in the bus or why the man shot at them.

Boris Rhein, interior minister of the state of Hesse, told reporters at the airport that the man approached the bus and shot a passenger standing in front of the bus and then killed the driver in his seat.

However, Linker said earlier that "it appears everything happened inside the bus."

Rhein said he is "consciously speaking of homicide and not an attack," adding that "at the moment nothing can be ruled out." He did not elaborate on the reasons.

Located in southern Germany, Frankfurt airport is one of the busiest transport hubs in Europe. The U.S. military has several bases in the Frankfurt region. Some shuttle buses are often used to transport U.S. servicemen between the bases and airports. 

VietNamNet/Xinhuanet