A £1 million drug factory was sniffed out by police at the scene of a harbour explosion.

Between 1,200 and 1,500 cannabis plants were found in a building in Littlehampton, after officers guarding the scene of Friday's fire in Rope Walk came across a suspicious smell.

Officers raided the storage building at about 3am on Sunday.

Inspector Gavin Whitehouse, of Sussex Police, said: “I've been with Sussex Police for 23 years and this is the biggest find that I have ever been involved in. It has got to be the biggest ever in Sussex.”

He said “community intelligence” led officers to the haul, after they noticed the plants' smell.

There were signs men had been living in the building.

Dan Van Tran, 43, and Huong Tien Le, 40, of Rope Walk, were charged with being concerned in the production of cannabis.

They appeared at Chichester Magistrates' Court on Tuesday.

Police are still investigating how long the factory had been operating and trying to trace the people responsible for leasing it and for the sale of the drugs.

Insp Whitehouse said: “It is part and parcel of an organised crime operation.

“It is our intention now as part of the ongoing investigation to identify who the key players are, to bring them to justice.”

The building was crammed with cannabis plants, mostly at the same level of growth.

Insp Whitehouse said: “It would be a massive crop at the end of it.

“The main thing is we have prevented a million pounds' worth of cannabis ending up on the streets of Sussex.”

Two people are due to stand trial on June 13 over the discovery of 1.8 tonnes of cannabis resin, worth an estimated £9 million, in Heathfield in October.

Paul Stevens, 44, of Sandy Cross, Heathfield, and Tracey Massey, 47, of Station Road, Hailsham, are due to appear at Lewes Crown Court accused of importing the class B drug.