Police investigating a gang selling large quantities of ecstasy around the world on the dark web said they have “dismantled” it following a series of raids.

The National Crime Agency (NCA) began inquiries last summer after parcels of MDMA destined for Europe, Asia and the US were intercepted.

Officers analysed encrypted messages to identify individuals involved in selling the drugs and laundering money using cryptocurrency.

The agency said 90 kilos of MDMA, 134 kilos of amphetamine and more than 6000 Diazepam/alprazolam tablets, with a combined street value of £4.3 million, have been recovered during the investigation.

Two men, aged 24 and 31, were arrested on Thursday in South Shields and Hebburn, South Tyneside, on suspicion of importing and supplying Class A, B and C drugs.

An address in Epsom, Surrey, was also searched, along with other addresses in South Shields.

Officers also seized mobile phones, computers and drug packaging paraphernalia in an operation which was supported by US law enforcement.

Officers discovered the drugs were being imported from Holland and then sold on the dark web under four handles – HundredsUK, Hundredsandthousands, Sundaefundae, and 100and1000s.

Packages containing MDMA, which were intercepted by NCA and Border Force officers in June and July last year, were destined for addresses in the UK, US, Israel, Norway, Thailand, Hong Kong and Kuala Lumpur.

NCA operations manager Martin Clarke said: “This action against an organised crime group supplying drugs via the dark web has dismantled a well-established operation.

“We have worked closely with partners in the US to target the individuals involved, who are ultimately preying on the vulnerable and destroying communities.

“This investigation shows that those who try to use the dark web and encrypted communication devices to anonymously commit crimes can be identified.

“There are two people from South Shields we are still seeking, who we believe are overseas.

“They know they are wanted and I would encourage them to hand themselves in.”