Three members of a gang accused of stealing from flatbed trucks have been arrested for theft and robbery.
Another gang member is on detention, and one is still at large, according to prosecutors of Baoshan District.
The first incident is alleged to have occurred on the night of December 1, when a truck driver surnamed Xi was transporting 14 copper sheets, weighing 2.5 tons, from Shanghai to Suzhou.
Prosecutors said the suspects managed to steal two of the sheets when the truck stopped at traffic lights.
The next day, another truck driver was targeted and beaten, although on this occasion the gang fled the scene empty-handed, prosecutors said.
As the suspects had used violence against the second driver, three of them were facing charges of robbery with violence as well as theft, prosecutors said.