Blast heard in Tehran's park, no casualties reported yet

A blast caused by an "unknown object" was heard in a park in north Tehran early on Saturday, Iranian state television reported.

There are no reports of casualties so far. "Just one explosion took place inside Mellat (People) Park," said Tehran Deputy Governor Hamid Reza Goudarzi.

An investigation into the cause of the incident is underway, said the governor, when asked whether the incident was an attack.