Kabul blast: 11 US citizens injured, death toll rises to 90

11 Americans were among the 400 people injured in the massive explosion that rocked a highly secure diplomatic area in Kabul on Wednesday, killing at least 90 people.

There were 11 U.S. citizens - all contract personnel - injured in the blast and one Afghan local guard was reported missing, Fox news reported a senior U.S. official as saying. Nine Afghan guards working for a U.S.-contracted security company were also killed.

No group has claimed responsibility for the blast but Afghanistan's National Directorate of Security (NDS) claimed that the bombing was planned by the Haqqani network in Pakistan and had help from Pakistan's intelligence agency, ISI.

The target of the explosion in the Wazir Akbar Khan area was not immediately known, but Public Health Ministry spokesperson Ismail Kawasi said most of the casualties were civilians, including women and children.

Germany's Foreign Minister Signmar Gabriel said employees of the German Embassy in Kabul were also wounded and an Afghan security guard was killed. The Foreign Ministry activated a crisis team to help deal with the aftermath

The intensity of the blast was such that windows were shattered in shops, restaurants and other buildings up to a half mile from the blast site.

The neighborhood is considered Kabul's safest area, with foreign embassies located in its vicinity. The German Embassy, the Foreign Ministry and the Presidential Palace are all in the area, as are the British and the Canadian embassies. The Chinese, Turkish and Iranian embassies are also located there.

The U.S Embassy and the NATO mission in Kabul are also near, about a kilometer away from the site.