Banning orders warning ahead of Exeter and Plymouth match
Any troublemakers at a derby between two Devon football clubs face "the very real risk" of a football banning order, Devon and Cornwall Police have said.
Exeter City is due to play Plymouth Argyle at home later.
More than 20 people were arrested when violence broke out between fans of the two clubs at a match in November.
Devon and Cornwall Police have given this latest match a category C security rating, which is the highest level.
Extra officers, dogs and police officers have also been drafted in from South Wales.
Superintendent Chris Singer said intelligence officers had been "working hard" to identify people suspected of wanting to cause problems.
Supt Singer told BBC News: "We don't want to approach the [match] policing with the past in mind but clearly we have to."
In a warning to potential troublemakers he said: "Ultimately you have the very real risk a football banning order will prevent you attending football matches in the future."
Football banning orders can last between three and 10 years.
A breach of one is punishable by up to six months in prison.
Julian Tagg, chief executive of Exeter City FC, said: "I think there's a very small minority where there's animosity.
"I think there's some exceptional fans here and Plymouth has the same.
"I think there's considerable rivalry and little animosity.
"But you've got to be careful."