Five deaths have so far been reported due to the fire at a rubber factory in the Horana area. 

The initial investigations have revealed that the explosion had occurred inside an Ammonia tank. 

Sources from the Horana Hospital said 10 people were receiving treatment due to the explosion. One, they said, is in critical condition. 

Eye-witness accounts said the accident occurred when a man fell into an ammonia tank at the factory. Four others who attempted to save him also died in the incident.

Further investigations are underway into the explosion.