THICK black smoke is engulfing swathes of the town as emergency services continue to battle against the fire in Ocado's Andover warehouse.

Pictures this afternoon showed the fire had spread to the other side of the facility from where it had appeared to originate in the early hours of Tuesday morning.

Walworth Roundabout and the entrance to Walworth Business Park from the A3093 were earlier blocked off by police cars and an evacuation has begun of nearby areas.

Queues of cars were seen trying to leave the estate amid reports the park had been evacuated.

Hampshire Fire and Rescue Service said earlier roday that crews had brought the blaze under control, following it being declared a major incident last night.

(Video by Anna Lucy)

However, this afternoon pictures and videos emerged of the smoke across Walworth Business Park escalating.

READ: Residents told to evacuate as smoke erupts from Ocado fire

Firefighters have been tackling the blaze for nearly 40 hours.

A couple living in St Mary Bourne told the Advertiser black clouds have appeared across their home since lunctime, with black parts of debris falling into their garden.

The smoke has reportedly been seen from as far as away Highclere, Tadley and Winchester.

WATCH: Drone footage shows extent of damage at Ocado site 

Leader of Test Valley Borough Council Councillor Phil North said environmental health officers are monitoring the air, as the fire service continues to advise residents to keep windows and doors closed in areas affected by the smoke.

Cllr North said: "I have seen various posts from Augusta Park residents and others concerned about the smoke cloud from the Ocado fire on the Walworth business park.

"Test Valley Borough Council has Environmental Health officers on the ground and the air is being frequently monitored.

"We have spoken to Hampshire Fire and Rescue Service and their advice remains to keep windows and doors closed in areas affected by the smoke.

Over 200 firefighters have attended the scene so far to tackle the blaze with resources coming from as far away as Watford.

READ: Firefighters tackle warehouse blaze at Ocado