British Transport Police are appealing for information after a bottle of hydrochloric acid was found on a Northern Rail train at Middlesbrough station shortly after 7 o'clock on Sunday evening.
The station was evacuated for a time and buses replaced train services.
4 fire appliances attended the incident along with 3 special appliances and 3 officers.It is believed the acid was in a soft drink bottle and caused the smell of burning when some of the liquid leaked from the container.
More top news
Rail fares in Britain are set to rise by 2.3% next year. Here is how the rise will affect commuters on routes across the country.
Lee Irving was picked on at school because of his learning difficulties and died a painful death at the hands of his killer
Two elderly residents have been attacked in their homes by three masked robbers armed with planks of wood in Durham.