The Iranian capital was rocked by heavy bombing once again in the early hours of the morning, according to reports on Wednesday.
Images shared on social media showed thick plumes of smoke rising above rooftops in the city's north-east.
An airstrike was reported in the Nobonyad district, where a defence industry complex is located. Explosions were also reported in other parts of the sprawling metropolis, which is home to around 15 million people.
In the city centre near Hafte Tir Square, residents described a fresh wave of attacks shortly before 6 am (0230 GMT).
"I jumped up like a frightened cat. I'm writing to you because it makes me feel alive," said prominent US-based citizen journalist Vahid, quoting a message he received from Tehran.
Vahid is a widely followed internet activist who gathers information from various sources and shares it online, often circumventing strict Iranian state censorship.
