The first photos from within a fire-damaged Melbourne tower covered in combustible cladding have been revealed as authorities raise issues of overcrowding inside the apartments.

Testing to confirm the make-up of exterior cladding on Spencer Street’s NEO 200 tower is yet to be completed, after a cigarette sparked a fire on a 22nd-floor balcony.

The address had previously been identified as ‘moderate risk’ due to its cladding and was one of more than 2000 inspected by the Victorian Building Authority.

Metropolitan Fire Brigade assistant chief officer Trent Curtain told reporters that fire crews noticed a range of fire safety issues inside apartments at the tower, including large amounts of combustible materials left on balconies and plastic covers over smoke alarms.

“We noticed in some apartments there were a large number of beds … which we think would be inconsistent with the use of the building,” he said.

Hundreds of residents have been evacuated from the Spencer Street complex for at least 48 hours following a City of Melbourne emergency order.

The council said it’s likely to take longer until the 40-storey building is declared safe to occupy, given the extent of damage.

It is understood residents will be permitted to re-enter the building for a short time on Wednesday morning.

An emergency relief centre has reopened at Melbourne Town Hall for those affected.