A 14-year-old boy has been bailed after reports of two suspected arson attacks in London Colney were received by the police.
Firefighters battled a suspected arson for nearly two hours after the contents of a Mercedes lorry parked in Five Acres went up in flames.
Police said the 12-ton lorry caught fire after someone ripped off the curtain of the lorry and set fire to the fruit and vegetables stored inside the vehicle.
The vehicle was owned by a greengrocer.
Hertfordshire Constabulary are not sure if there was more than one person involved.
Police and firefighters were also called at 7.20pm after a fire was started in a disused garage, which is owned by St Albans City Council.
The 14-year-old must reappear at Hatfield police station on Wednesday, June 25.