The explosion of a chlorine gas canister being transported by a truck in western Iran has injured 217 people but caused no deaths, state news agency IRNA reported.

The blast struck late Friday in Chardavol county in Ilam province, the news agency said.

The head of the province's medical university, Mohammad Karimian, told IRNA driver "carelessness" was suspected.

The incident is the latest in a series of fires and explosions that have hit military and civilian sites across Iran since June.