A San Francisco-bound Boeing 777 operated by Japan Airlines (JAL) returned to Tokyo International Airport at Haneda Tuesday due to a problem in its hydraulic system, news reports said. The JAL jetliner carrying 249 passengers and crew members landed at the airport safely, dpa quoted Jiji press as reporting. The jet left the Haneda airport around 0:20 am (1520 GMT Monday). When it was flying at around 360 kilometres north-east of Tokyo, an indicator showed an abnormality in the hydraulic system, the report said, citing JAL. The plane then flew back and arrived at the airport at 4:10 am. Oil believed to come from the hydraulic system leaked during landing, prompting the runway to be closed temporarily, Jiji reported. JAL is investigating the incident.