The four mining engineers who returned to Japan on Tuesday night after being held hostage for more than two months by Islamic rebels in Central Asia do not suffer from any serious health problems, doctors said Wednesday after the four underwent medical checkups at Tokyo hospitals.

The doctors, however, also said the engineers will be hospitalized for several days for further checkups.

The four were sent to hospitals immediately after they arrived at Narita airport and saw their families there for the first time since they were dispatched to Kyrgyzstan four months ago.