Anybody who carries out arson for money could face "significant" sentences, police have warned, as they arrested eight people after a series of attacks across London.
Seven of the arrests, all carried out in the past 48 hours, are part of a proactive investigation into alleged conspiracy to commit arson, the Met Police have said.
The force says that it is believed the intended target is related to the Jewish community but it is not at this moment known.
Deputy Assistant Commissioner Vicki Evans, the Senior National Co-ordinator of Counter Terrorism Policing, said the use of criminal proxies to carry out attacks was a "key line of inquiry".
Three men, aged 24, 25 and 26, were detained in Harpenden shortly after 9pm on Sunday 19 April. They were taken into custody before being released on bail.
The day after, on Monday, a 25-year-old man was arrested in Stevenage.
A 26-year-old man, and two women, aged 50 and 59, were also arrested in a car near Birmingham. They have all been taken to a London police station where they currently remain in custody.
This morning, another man, aged 39, was arrested at an address in Ealing in relation to an investigation following the discovery of jars of a non-hazardous substance in Kensington Gardens on Friday 17 April.
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A search has also been carried out in east London.
Counter terror police have made a total of 23 arrests since an attack on Jewish run ambulances in Golders Green, north London, back in March.
Eight of those have been charged with arson-related offences, while 13 remain in custody or on bail under active police investigation.
'The stakes are high'
Ms Evans said officers would be "relentless" in tracking down those responsible.
She said: "Our message is clear, we will not tolerate this intimidation of our communities, and will pursue those responsible.
"One of our key lines of inquiry is whether criminal proxies - that is to say people being paid money to carry out a crime - are being used to commit any of these arsons.
"While our investigations into this are still ongoing, my message to anyone even considering getting involved in this type of activity is this: the stakes are high and it is absolutely not worth the risk.
"When we identify you, we will seek to prosecute you. This will include considering offences under the National Security Act which comes with a significant sentence and lifetime restrictions.
"We will not rest until all those responsible for these acts are held to full account."
(c) Sky News 2026: Police warn people not to carry out arson for money after eight arrested by counter terror police
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