The airport's management tweeted that the blast took place at the second-busiest airport of the country at around 2:20 pm. Authorities said that it is likely that the blast has been caused by some sort of homemade explosive.
The injured were admitted to hospital but nothing is known about their condition. Management said that no flight was disrupted due to the explosion.
Passengers, who were waiting to board their flight when the explosion happened, said that passengers started running for cover after hearing a loud noise.
Pudong serves international flights and is also a hub for two major domestic airlines.