Col. Mansour Al-Johani, spokesman for the Civil Defense, said the pipe suddenly exploded without warning while the three men were carrying out routine maintenance.

He added that the Civil Defense used divers to recover the two men’s bodies. “The third man was taken to hospital and is in serious condition. An investigation has been launched to ascertain what happened,” he said.

Eyewitnesses, who did not want their names to be published, said the men, who worked for a maintenance company, were not properly trained on dealing with sewage networks.