Northumbria Police are warning young people of the consequences of setting deliberate fires in farmers fields.
The warning comes after a number of incidents where hay has been set on fire in farmers fields in Sunderland and South Tyneside, causing a substantial amount of damage.
Officers are carrying out enquiries to identify those responsible and are warning starting anti-social fires could have far reaching consequences.
Acting Neighbourhood Inspector Julie Beattie said: "Youths may think it is a bit of fun to set fire to hay and start fires in fields, however I want to warn them that what they are doing is incredibly dangerous and the consequences could be far reaching.
"We know fire is dangerous and it does not take much for a hay fire to spread with the potential to not just cause substantial damage but seriously injure or even kill someone.
"If that happens those who are responsible will face serious consequences.
"We believe those who are responsible are young children and would ask their parents make sure they are aware of the risk involved in setting fires and know where they are and what they are doing when they are out playing."
Anyone with information about those who may be responsible are asked to contact Northumbria Police on 101 quoting reference 933 060916 or Crimestoppers anonymously on 0800 555 111.