No suspicious vehicles have been captured by security cameras installed around the areas where the body of a slain 9-year-old Vietnamese girl was found near a drainage ditch in Chiba Prefecture, NHK reported, quoting investigative sources.

Police believe the girl, Le Thi Nhat Linh, was strangled elsewhere and dumped at the spot where her body was found Sunday in Abiko, saying there were no signs of a struggle in the grass field.

According to NHK, the police have analyzed the images taken by security cameras along major roads connecting areas near her home in Matsudo and the field in Abiko. But the police have so far detected no suspicious vehicles, NHK said.

There are other local and narrower roads linking the areas without security cameras, including those mainly used by farmers, leading the police to believe the perpetrator has local geographical knowledge, NHK reported.

According to the police, the naked body of the girl was found by a fisherman but there were no clothes or other belongings at the site. Her school bag was found in a separate area.

The girl left home but failed to show up at school on March 24, the last day of the school year, which runs from April to March. The site where her body was found is about 10 km from the school.