Turkey announced on Sunday a day of national mourning after attacks in Istanbul, Dogan News Agency reported.

Late on Saturday, two explosions rocked central Istanbul near Besiktas's Vodafone Arena Stadium, leaving 38 people killed and 155 others wounded.

Interior Minister Suleyman Soylu said seven civilians are among the dead, while 30 others are police officers and one of the victims hasn't yet to be identified.

Turkish President Recep Tayyip Erdogan postponed a visit to Kazakhstan, which was scheduled to take place on Sunday, due to the terror attack.

On his twitter account, Erdogan vowed to "continue our struggle" despite more blood to be shed.

Istanbul, the Turkey's largest city, and Ankara, the country's national capital, have come under a spate of deadly attacks over the past year amid a worsening security situation.

Istanbul was last attacked in late June, when three suicide bombers assaulted the city's major international airport and killed 45 people.

source: Xinhua