Police in Manchester battling an epidemic of the use of spice attended nearly 60 incidents related to the drug in the city centre in one weekend.

Authorities in the city have reported a surge in the use of the synthetic cannabinoid, which is said to induce a zombie-like state.

Drug dealers target rough sleepers with ‘spice’ linked to prison violence Read more

A ban on the supply and production of spice and other novel psychoactive substances came into force with the Psychoactive Substances Act 2016. The drug was previously legally available to buy in shops and online.

Greater Manchester police imposed a 48-hour dispersal order on the city centre on Friday and Saturday, launching special patrols and making scores of arrests to remove anyone suspected of taking or supplying the drug.

The force said there were 58 spice-related incidents in the centre of the city on Friday, Saturday and Sunday, resulting in eight arrests. The three days also saw 23 incidents to which an ambulance was called and 18 dispersal orders or directions to leave issued.

Fifty-one arrests have been made in the past three weeks as part of Operation Mandera, the police crackdown on supply of the drug.

Most of the incidents were in the Piccadilly area of the city centre – described as a dystopian nightmare by the Manchester Evening News – which serves as a transport and shopping hub.

The use of spice can cause hallucinations, psychosis, muscle weakness and paranoia. Videos of users have gone viral, with some shown twitching or in a catatonic state.

When the drug first appeared in the UK it was often described as having effects similar to those of cannabis, but experts have described such a comparison as dangerous as the effects of spice are much more extreme and unpredictable.

Dr Robert Ralphs, a senior lecturer in criminology at Manchester Metropolitan University, who has conducted research into the use of spice among the homeless population in the city, said users reported that the drug was equally or more addictive than heroin. “It’s quite common for people to say it’s overtaken their heroin or methadone addiction,” he said.

Charity workers say the drug has proven popular among rough sleepers because it is cheap – £5 for half a gram – and strong, allowing them to “self-medicate” and forget the difficulties in their lives. A survey conducted the charity Homeless Link last year found that more than 90% of rough sleepers in Manchester had tried spice.

“When you first start using [spice] you only need a pin head and you can get 30 to 40 joints out of a gram,” says Ralphs. “But people then build up tolerance and end up smoking six, seven, eight grams a day ... they can find themselves spending £40 to £50 a day on it.”

Phil Spurgeon, a city centre inspector with Greater Manchester police, questioned the wisdom of the ban on the drug. “Spice has been around for the past two or three years in different guises,” he said. “I’m not being judgmental about the legislation, but the reality with the Psychoactive Substances Act is that it has shifted supply on to the streets.

“The product was probably more consistent in the head shops. Now it’s more varied, the makeup is constantly changing. That’s why we’re seeing people collapsing, as the drug becomes more potent.”

Ch Supt Wasim Chaudhry, also from the force’s city centre team, said they could not afford for the problem with spice to get any worse. “We have increased the number of specially trained officers to try and combat the issues and help those using spice to access the support they need but to also ensure that danger of spice is clearly communicated,” he said.

“Those who take spice are often left incapacitated or seriously ill and need the help of our partners in the NHS and Ambulance Service. They can also become aggressive and become a danger to themselves and others.

“The truth is, tackling the issues caused by spice is putting pressure on public services and is taking up a lot of our resources. Particularly in Manchester city centre.”

• This article was amended on 14 April 2017. An earlier version said Psychoactive Substances Act 2016 did not ban possession of spice and other novel psychoactive substances. That is correct, but “third generation” synthetic cannabinoids, such as those found in spice, were reclassified as class B drugs under the Misuse of Drugs Act last December, making possession a criminal offence.