Beijing: A series of explosions rocked a 30-storey condominium-cum-shopping mall in northeast China on Friday, killing at least one person and injuring another in an incident being treated as a criminal case.

The first blast happened at around 3:13 pm (local time) when the fire brigade in China's Changchun city, provincial capital of Jilin province, received a call saying that a car had exploded in the basement of the Wanda Shopping Plaza building, the Hong Kong based South China Morning Post reported.

Three minutes later, another explosion shattered windows on the building's 30th floor. It was unclear what caused the explosions.

City authorities confirmed that one person was killed and another injured so far.

Eyewitnesses reported hearing over 20 explosions and people were evacuated from buildings surrounding the Wanda Plaza.

The city authorities are treating the explosions as a criminal case.

"Preliminary investigations by public security agencies show that this is a criminal case, work to handle the situation is proceeding in an orderly manner," said the city authorities on their Weibo account.

A witness who was dining at a restaurant in Wanda Plaza on Hongqi Street told the Beijing Youth Daily that people were asked to evacuate immediately.

There must have been more than 20 explosions. The shopping mall asked people over the public address system to leave right away, and we ran for our lives, a witness, identified only by her family name Zhang, was quoted as saying.

She said she saw sparks around her as she was running out.

A video clip circulating online, showed a bright beam of light accompanied by a loud bang from a room in a higher floor of the Wanda building, and another explosion and heavy smoke on the ground, with people running for safety.

Another video showed several smaller explosions in front of the building billowing smoke.

Authorities are still investigating the cause of the explosions.