An investigation into the cause of a factory blaze which sparked an asbestos scare has been delayed.

Police believe it will be up to three weeks before they can get into the blackened shell of the Hosiden Bessen warehouse in Victoria Road, Portslade.

Structural engineers will need to examine the remains of the building, which has partially collapsed in on itself.

The 1000C (1832F) inferno left the warehouse's main brick walls badly cracked and bowed.

Experts will decide in the next few days if the building must be demolished before the investigation can begin.

Meanwhile, a team of asbestos disposal experts wearing anti-contamination masks began the task of cleaning up debris around the site.

Detective Inspector Graham Pratt said: "We have delayed bringing in the Home Office forensic scientist because of the dangerous state of the building.

"It has collapsed in on itself and will need to be made safe before anyone can go in."

It is understood that investigators are looking at the possibility of an electrical fault.

Hundreds of people gathered in Victoria Road as fire crews battled fierce flames and billowing black smoke.

There were fears the area had been contaminated by asbestos in the factory's roof but tests revealed no detectable trace of asbestos in air and debris samples.

Tim Nichols, Brighton and Hove City Council's environmental services director, said a hotline set up to deal with debris from the fire found in streets and gardens around the area had received 100 calls.

Residents have been warned not to touch debris and to stop children or pets from playing in gardens affected by ash.

Mr Nichols said: "One call was from someone worried about whether they could eat fruit or vegetables they had grown in their garden.

"As long as they are washed thoroughly first, they should be perfectly safe."

He said the priority had been to clear debris and to check that the two nearby schools had not been contaminated.

St Mary's and Benfield Junior Schools were given the all-clear.

The 24-hour hotline number for anyone needing debris from the blaze removed is 07984 037042. Anyone with health concerns should phone 01273 292436.