The death toll following the accident at a rubber factory in Horana, caused by an employee falling into an ammonia tank, has climbed to five, the police spokesman said.
The factory employee who fell into the ammonia tank and four villagers who attempted to rescue him have died.
Several other persons who were unconscious have been admitted to the Horana Hospital
It was previously reported that one person died after falling into an ammonia tank at the rubber factory in Ballapitiya while another 14 persons who tried to rescue him have been hospitalised.
Police said that the incident had occurred at around 1.20pm today (19) when a factory employee fell into the tank, which collects ammonia wastage from the rubbery factory, while attempting to clean the tank.
A group of villagers, residents of the area, had attempted to rescue him, however some 15 of them had collapsed unconscious possible due to breathing in the toxic gas and were rushed to hospital. Four of the villagers had also died.
Horana Police is conducting further investigations.