Bonfire Night has become a "curse" for some Liverpool residents, as it is being "hijacked" by organised gangs fly-tipping, a councillor has said.
In the past week, police said more than 55 tonnes of rubbish had been removed from sites that had "dangerously oversized" bonfires built near homes.
Open plots of land have also been used as "dumping grounds", councillor Laura Robertson-Collins said.
"The issue has been building for some years now," she added.
In a blog, Ms Robertson-Collins said: "Last year the scale and proximity to homes of some of these illegal bonfires posed a real threat to life.
"The danger is also very real to fire officers who have to put out these potential death traps that have at times contained explosive items, such as pressurised containers."
Almost 100 tonnes of waste were removed last year, but there were still "numerous fires which proved a huge drain on public finances in putting them out and cleaning the sites".
Land was left "scarred for months afterwards - and the soil beneath, that is contaminated for years to come".
"This is fly-tipping on a criminal scale. And our crews have been threatened at some of these sites, needing to return under police escort," she said.
Drawing a comparison with Eurovision in May, she said crews collected 50 tonnes of waste during a three-week operation, when the city attracted about 500,000 visitors.
The councillor said trading standards officers would be monitoring any illegal sales of fireworks and prosecuting offenders, adding: "This is not about being anti-fun. This is about being safe."
Merseyside Police has put in eight dispersal zones across the force area.
The zones give officers the power "to direct people engaging in anti-social behaviour or are likely to become involved in such incidents" to leave the areas for up to two days.
'Real safety concerns'
Ch Insp Duncan Swan said: "The purpose of the dispersal order is to break up those depositing wood and waste material which contribute to anti-social behaviour.
"Just in the last week more than 55 tonnes of rubbish have been cleared from sites which have been dangerously oversized bonfires built close to homes and in public areas.
"I must stress that these unofficial bonfires pose real safety concerns to the public."