Petersfield Festival Hall's fire alarm was sounded at 2pm on Friday and fire engines arrived shortly afterwards.

Thick smoke billowed from offices on the first floor and was still seen pouring out of the building at 3.15pm.

Firefighters with breathing apparatus moved in to tackle the blaze and scaled a ladder to reach the roof.

Petersfield town clerk Neil Hitch said: "Fire fighters have entered the building up the fire escape and the main staircase, but they are still struggling to get close to the fire because it is too hot."

Early indications suggest it began in a room used by a business that rents office space at the Festival Hall.

About 100 costumes used by theatre group Petersfield Hi-Lights, who were scheduled to perform Calamity Jane at the venue on Friday evening, are expected to have been damaged by the smoke.

A crowd of onlookers gathered on the road side were moved away by firefighters who had concerned about the damaging effects of the smoke.

Yolanda Lacey, a part-time employee at the hall, was just leaving to pick up her son from school when the fire broke out.

She said: "I saw a lot of smoke and everyone was rushing around and we were told to evacuate the building. The fire is all over the roof, where workmen had been working. The smoke is very thick and smells like rubber."