South Korea's immigration office said Friday it is searching for a Chinese sailor who illegally entered the country from a port located in western Seoul, marking the third time for immigration security to be breached this year at the area. 

A 33-year-old Chinese crewman allegedly crossed over a 2.7-meter security fence at the western port city of Incheon at 12:56 a.m. using a 3-meter ladder. 

Investigators said while the fences have alarms that sound when physical contact is made through infrared sensors, the fugitive successfully climbed the wall as the ladder allowed him to avoid touching it directly.

The Incheon Port Security and the police said they is searching for the whereabouts of the man.

On Jan. 6, a 33-year-old Vietnamese man also entered South Korea by cutting through a security wall at another port located north of Incheon. Another Chinese man also jumped over a fence on Jan. 17. The two have not yet been arrested.

(Yonhap)