Police have said they are not treating the drivers of a Ford Transit van as suspects after a theft of potentially lethal drugs.

Thieves stole 20 to 23 boxes of syringes filled with the drug Enbrel, which is used to treat Rheumatoid Arthritis from a van in Fore Street, Upper Edmonton on Wednesday at about 5.30pm.

A courier was collecting the drugs from a chemist but as he returned to the vehicle after collecting more boxes, he found the loaded boxes had been stolen.

The drug can be lethal if injected into the bloodstream or administered incorrectly.

Officers in Enfield are making more enquiries into the CCTV footage from the area.

Acting Detective Sergeant Stuart Miller, Enfield Borough Police, said: “It has been a number of hours since the boxes were stolen and our investigations have moved on.

“We now do not believe that the white Transit van and its occupants were involved in this theft and are no longer appealing for information about it.

“However the drugs are still outstanding and I wish to take the opportunity to appeal again to anyone who may have seen anyone acting suspiciously outside the pharmacy at the time the boxes were stolen or anyone who may have been offered the drugs to contact the police.”

A spokeswoman of Pfizer Ltd, licence holder for Enbrel said: "We are aware of reports of the theft of Enbrel (etanercept) pre-filled syringes from a delivery van in North London and will cooperate with any enquiries as necessary.

Patient safety is of utmost importance to Pfizer. Patients should only take medicines that have been prescribed to them by their healthcare professional and should follow the relevant safety information provided."