A Kenyan man alleged to have killed his girlfriend at an airport in the United States of America (USA) before escaping has been arrested in Westlands Nairobi.

The 40-year-old Kevin Kang'ethe was arrested on Monday night and is detained at Gigiri Police Station as investigations continue.

He is accused of killing a 31-year-old Kenyan woman based in Whitman, Massachusetts, whose body was discovered inside a vehicle at Boston's Logan Airport in November last year.

Margaret Mbitu, the deceased, was employed at BAMSI, a nonprofit organization with its headquarters located in Brockton, when she was originally reported missing.

The victim was last observed driving a white SUV out of BAMSI's grounds, according to the organization's missing persons report.

Evidence retrieved from the car registered in Mbitu's name leads authorities to think that Kevin Kang'ethe killed him.

Kang'ethe is believed to have fled to Kenya following the incident, but area police have yet to establish the motive behind the suspected murder.