SYDNEY, Dec. 15  -- The Chinese Embassy and Chinese Consulate in Australia warned Chinese citizens on Monday to stay away from the hostage crisis that is taking place at a cafe in the city center of Sydney.

The siege at the cafe began Monday morning after an armed man, showing Islamic flags, took up to dozens of people hostage.

The Chinese mission issued an emergency warning aimed at protecting Chinese citizens living in Sydney.

The embassy said Martin Place, where the cafe siege is taking place, is in the city center and it is an important business and financial hub, having a train station and attracting thousands of shoppers and tourists every day.

The Sydney CBD is a popular destination for international tourists, including an increasing number of Chinese tourists and Chinese students.

"We have been in close contact with the Australian federal government in order to understand the situation, especially to find out if there were any Chinese citizens held hostage," the office said in a statement.

The Chinese consulate general's office in Sydney said it was in contact with New South Wales (NSW) police to verify whether there were Chinese citizens involved in the siege.

"NSW police has promised that if there were Chinese hostages involved, they would immediately notify the consulate," a spokesperson said.

Chinese Embassy in Australia and Chinese Consulate General in Sydney has informed Chinese citizens that they can call special emergency numbers for further updates.

The Chinese Embassy emergency telephone number is: 0061- 418452387, and the Chinese Consulate General in Sydney's 24-hour emergency number is: 0061-413647168.