Japan police chief climbs down over questionable cyber arrests

TOKYO (AFP) - Japan's most senior policeman began an embarrassing climbdown on Thursday after his officers arrested four people over cyber threats issued when their computers were apparently hacked.

E-mails containing threats to attack targets including a school and a kindergarten attended by Emperor Akihito's grandchildren were sent from infected computers in different parts of the country.

The computer owners were arrested and held, in one case for several weeks, in a system where custody conditions are harsher than those in other developed countries and where police rely heavily on confessions.

Two of the suspects reportedly admitted sending the e-mails before a broadcaster and a lawyer received an anonymous message containing information investigators conceded could only have been known by the real culprit.