Radioactive material stolen from van in Lancashire The missing canister, marked with the black and yellow radiation trefoil, contains iridium-192, used to detect flaws in metal or as part of radiotherapy. Photograph: Martin Diebel/Getty Images/fStop Police have warned thieves in Lancashire that they could be in danger from a canister of radioactive material if they breach its seals without realising what is inside. Officers in Bacup issued an appeal for the return of the small container, which is believed to house a small amount of iridium-192 and was taken from a Peugeot panel van parked in New Line street in the town over the weekend. Iridium-192 is a radioactive isotope normally used to detect flaws in metal or as part of radiotherapy treatment. The canister is made of lead and marked with the black and yellow radiation trefoil, but Chief Inspector Russ Procter of Lancashire police said that it could still pose a danger. He said: "It is important that this material is located as soon as possible. I would ask the public, especially in the Rossendale area, to keep an eye out for this canister and if they locate it then to call the police who will come and deal with it. I would also appeal directly to the people who have stolen this. They may have no idea what it is that they have in their possession or they may have discarded it somewhere. If that is the case then I would ask them to contact us or call Crimestoppers on 0800 555 111 anonymously. The Health Protection Agency urged anyone coming into contact with the cylinder to leave it where it is and alert the police. A spokesman said: "It will not pose a risk to the public if it remains contained. However, if the material is outside of its protection packaging, anyone who has come into prolonged physical contact, such as keeping it in a pocket, should seek medical assistance. If you see this package you should immediately inform the police, do not touch it and keep away.