TOKYO - Japanese police plan to arrest on suspicion of attempted murder four children of US military personnel after a motorcyclist was badly injured by a rope stretched across a road, it was reported Wednesday.

The 23-year-old woman suffered a fractured skull after she was caught by the rope and thrown off her moped near western Tokyo's US Yokota Air Base on August 13, said the Yomiuri Shimbun daily and other media.

The woman later told police she saw four foreigners shortly before the incident, according to the reports citing unnamed sources.

A surveillance camera recorded images of three boys and one girl in the area at the time, and the four allegedly acted 'suspiciously' when later questioned by police.

Police have obtained arrest warrants and planned to take the four teenagers, reportedly aged between 15 and 18, into custody as early as this week, the reports said. Tokyo police declined to comment when contacted by AFP.