Eyewitnesses report a large explosion in a gas storage station in the northern Chinese port city of Tianjin Wednesday night.

Chinese news reports that a blast wave reached several kilometers and that at least 50 people were injured.

According to official state channel China Central Television, a shipment of explosives blew up around 11:30 pm local time (4:30 pm GMT).

Another state news agency, Xinhua, reports that at least two firefighters are missing.