Vandals armed with explosives have restarted a dangerous campaign of blowing up parking meters in a historic market town.
Fourteen machines have been attacked in Lewes, East Sussex, since mid-September, causing more than £20,000 of damage.
Police chiefs and councillors say they are amazed no one has been injured and warned whoever is responsible that they could face jail.
The town - famous for its large annual Guy Fawkes night display - has been targeted by vandals systematically blowing up meters in the past.
It started in 2004 after the local council introduced on-street parking charges following complaints of congestion in the county town's narrow streets.
In the two years that followed, the culprits caused £300,000 damage by destroying more than 200 meters, leading to higher permit charges and increased pay and display parking costs for residents and visitors.
Now it appears the dangerous and costly campaign has intensified again, with one machine - in Southover High Street - being completely destroyed.
Others will be repaired or have been fixed already. No money has been stolen from the machines, which are valued at about £3,000 each.
A reward of £1,250 has been put up by East Sussex County Council, Sussex Police and Lewes District Council for information leading to the arrest and conviction of those responsible.
Chief Inspector Natalie Moloney, Lewes district policing commander, said: "I can't believe anyone would be so reckless as to carry out such potentially dangerous acts.
"I'm amazed someone hasn't been injured.
"This is a serious spree of costly vandalism and we are determined to find out who is responsible.
"Someone knows who is doing this and it is important that they help us put a stop to it now before someone gets seriously injured."
Carl Maynard, the county council's economy, transport and environment spokesman, said: "Whoever committed this mindless crime should know they risk jail.
"As well as the potential to seriously injure a passer-by, this vandalism costs the people of Lewes, who will end up footing the bill.
"Repairs will cost at least £20,000, which means we are £20,000 further away from being able to put any surplus from the scheme toward transport improvements in the town."
Lewes District Council leader Tony Nicholson said: "We fully support the police in their call for information. This vandalism is dangerous and we do not want to see anyone hurt as a result of thoughtless action."
The first new attack was on September 16 when explosives were placed inside a machine in Grange Road. The latest incident was recorded on November 21 at White Hill.
Anyone with information is asked to call Sussex Police on 101 or Crimestoppers anonymously on 0800 555111.