A 23-year-old South Korean student was molested on a bus in the eastern Indian city of Kolkata Monday allegedly by her co-passenger, a senior police official said.

"The foreigner was traveling alone on the bus when the incident happened this morning. We have arrested the South Korean woman's co-passenger after she complained of sexual assault to traffic policemen," he said, on condition of anonymity.

A probe has been ordered into the incident, the official added.

Safety of women in India which has been a cause of concern since December last year when a 23-year-old Delhi University medical student was brutally and fatally gangraped by six men on a moving bus in the national capital.

Last week, a British tourist jumped off the balcony of her hotel room in the northern Indian tourist town of Agra to escape a rape bid by the hotel owner. This incident came days after a Swiss woman was allegedly gangraped while on a cycling tour with her husband in the central state of Madhya Pradesh.