POLICE raided a cannabis factory in Headington, Oxford, today.

At about 8.30am, officers entered the three-storey house after receiving a tip-off.

Once inside they found four large rooms filled with cannabis plants.

No one was in the property but police said there were signs someone had been staying at the address.

Engineers from Southern Electric have been called in to make the property safe after police found growers had illegally rerouted the mains to avoid detection and paying for power.