KHOST, Afghanistan, Nov. 23 (Xinhua) -- At least nine people have been confirmed dead and 25 others sustained injuries in a blast that rocked a mosque of national army in Afghanistan's eastern Khost province on Friday, an army officer in the province Captain Abdullah said.

"The blast took place in a mosque of an army battalion when people gathered to offer Friday congregation, leaving nine persons dead and injuring 25 others," Abdullah told Xinhua.

Without providing more details, the official added that investigation is underway.

Confirming the incident, spokesman for provincial government, Talib Mangal also said that nine people had been killed and 25 others injured.

The security forces have cordoned off the area and do not allow journalists to get access to the site of the incident.

However, locals believe that the blast might be suicide bombing and the casualties could be higher than reported.

Anti-government militants have increased activities mostly in the shape of deadly suicide bombings.

A suicide attack against a meeting of clerics in a hotel in Kabul last week had left more than 50 people dead and injured over 90 others.