Police were called at 11:09hrs on Thursday 5 June to The Shard, St Thomas Street, SE1 after London Fire Brigade were called to reports of a fire at the premises.
Police, London Fire Brigade and London Ambulance Service attended the fire which is beleived to be in the basement of The Shard.
A full evacuation is now underway.
No reported injuries at this time. No arrests. Enquries re cause of fire are ongoing.
More top news
The grazing is part of a wildlife scheme to help a flower meadow and the insects that rely on it
A lamp in the tower which houses Big Ben is to be switched off for the first time in more than 70 years.
Sir Bruce entertained audiences for more than seven decades.