A man blew himself up Sunday at the gate of an army base in Pakistan's northwest, killing at least 11 people, including four soldiers, officials said.
There was no immediate claim of responsibility.
The suicide bomber struck at the gate of the Punjab Regimental Center in the city of Mardan, about 30 miles east of Peshawar. Most of the casualties were at a nearby market.
Police Chief Akhtar Ali Shah said 22 people were wounded.
Ehsanullah Khan, 25, who works in a music shop in the market, helped take the injured to a hospital in Peshawar, capital of North-West Frontier Province.
"I was busy dealing with a customer when a big bang shattered everything," Khan said. "A piece of broken glass left a deep cut on my arm, and I rushed out in panic."
Pakistan's northwest, which borders Afghanistan, is considered a haven for militants with links to the Taliban and Al Qaeda.