Watch: Suicide bomb attack in Kabul's diplomatic area; Islamic State claims responsibility

A suicide bomber riding a motorcycle blew himself up inside Kabul's heavily fortified diplomatic zone killing eight people on Tuesday afternoon.

"Our initial information shows the suicide attacker was on a motorcycle. He made it through the first checkpoint but was stopped at the second checkpoint and detonated," defense ministry spokesman Dawlat Waziri told AFP. 

The Islamic State claimed responsibility for the attack, Reuters reported.

"We don't know the target but it happened a few meters from the defence ministry's foreign relations office. No casualties to our personnel," the defense ministry spokesman said.

Security forces have cordoned off the Green Zone in Kabul after the bombing rocked the diplomatic zone.

Reuters reported there were numerous casualties, quoting Afghan officials.

A Reuters television reported at least eight people appeared to have been killed, besides several wounded at the explosion site in the city's Wazir Akbar Khan area.

At least 10 people were wounded in the attack.