AVA- According to reports, the explosion on Friday targeted members of the 2nd regiment of the Afghan national army, as they held their Friday prayers inside a military base.
Reuters reported that at least 50 people were wounded.
Sakhi Sardar, head of the hospital in Khost said most of the wounded were being treated for devastating shrapnel wounds.
The blast may have been set off by a suicide bomber or a remotely detonated bomb but nothing was officially confirmed and details were sketchy.
There was no immediate claim of responsibility for the attack, but the ISIS terrorist group has previously claimed most suicide attacks on mosques.
President Ashraf Ghani condemned the attack as "un-Islamic" and "inhumane".
The explosion came just days after a suicide bomber killed 55 religious scholars gathered in the Afghan capital, Kabul, to celebrate the holiday marking the birth of Islam's Prophet Muhammad.
The Taliban denied involvement in that bombing, which also wounded 94 people.
The attack was the latest in a relentless, near-daily onslaughts in Afghanistan, where the Taliban regularly target Afghan military and police forces throughout the country.
Friday's explosion comes as Afghan security forces suffer record casualties, which experts warn have reached unsustainable levels as the Taliban maintain the upper hand in the war.
Since the start of 2015, when local forces took over from US-led NATO combat troops to secure the country, nearly 30,000 Afghan soldiers and police have been killed, President Ghani revealed this month -- a figure far higher than anything previously acknowledged.
That is an average of around 20 soldiers killed per day.
Saturday 24 November 2018 00:02