Turkish Interior Minister Ali Yerlikaya on Tuesday said a man and a woman had been killed in an "attempt to attack" a security checkpoint at a court building in the Caglayan district.

The pair were believed to be affiliated with the leftist DHKP-C militant group, which has been involved in a campaign against the Turkish state since the 1980s.

What we know so far about the attack

Five people, including three police officers, were said to have been injured in the incident.

"I congratulate our heroic police officers. I wish a speedy recovery to our injured," Yerlikaya said, adding that officers had prevented a "treacherous attack."

Footage showed two bodies lying on the ground outside the main entrance to the courthouse.

The DHKP-C, which is considered a terrorist organization in Turkey, the United States, and the European Union, has been largely inactive in recent years. The group took a prosecutor hostage at the same court in March 2015, demanding information about the killing of a teenager by police during protests against the government.

The building, which is also known as the Istanbul Justice Palace, is a huge court complex used to try serious crimes, including terror charges.

Turkey has started to to emerge from a violent period that started about a decade ago when it was hit by repeated bombings and other attacks. The incidents have been linked to jihadist fighters and Kurdish militants.

While the attacks have largely died down, both Istanbul and the Turkish capital, Ankara, remain on high alert.

The attack took place as Turkey commemorated the anniversary of an earthquake that killed thousands of people.

rc/kb (AP, Reuters)