across the northwest and to other parts of the country, according to officials.
Pools of blood and charred pieces of human flesh littered the roadside, along with at least 20 burnt vehicles, said an AFP reporter. Clothes, school books, children's shoes and burqas lay everywhere.
Jamrud is in Khyber district, which is part of Pakistan's semi-autonomous tribal belt where the Taliban and Al-Qaeda-linked groups have strongholds.
A government office of the district administration was around 100 metres from where the bomb detonated but was not damaged in the attack, according to an AFP reporter.
"At least 16 people were killed and 71 others wounded in the blast caused by an explosive-laden car, which had been parked very close to the waiting area for passengers," Khyber's most senior administration official, Mutahir Zeb, told AFP.
He said ordinary civilians and not the government office, some distance from the explosion, were the target.
"We are still are ascertaining what procedure was exactly used to blow up the vehicle," he said.
Local administration official Jehangir Azam also confirmed that 16 people died.
"The blast also damaged 10 vehicles and more than 15 shops in the market," Azam said.
Officials had earlier said 12 people were killed.
Two intelligence officials, speaking on condition of anonymity, said the explosives had been packed into a Suzuki Alto vehicle.
Pakistan suffers frequent bomb and suicide attacks blamed on Islamist militant groups. Its troops have for years been fighting against homegrown armed groups in the tribal belt.
On Saturday, a suicide squad of five targeted the airport in Peshawar, the main northwestern city close to Jamrud, killing five civilians and blowing a hole in the perimeter wall.
The assault, claimed by the Pakistani Taliban, sparked prolonged gunfire and forced authorities to close the airport, a commercial hub and Pakistan Air Force (PAF) base on the edge of the tribal belt.
It was the second Islamist militant attack in four months on a military air base in nuclear-armed Pakistan.
On Sunday, a policeman and five militants were killed following gun-battles between security forces and militants suspected of having been involved in the airport attack, security officials said.
The government says more than 35,000 people have been killed as a result of terrorism in the country since the 9/11 attacks on the United States.
There has, however, been a noticeable decline in the number and severity of attacks since 2009, when the Pakistan army fought major operations against local Taliban in the northwestern district of Swat and the tribal district of South Waziristan.
According to an AFP tally there have been more than 100 bombings, killing 550 people, so far this year, compared to 203 recorded in 2009, when the death toll was tallied at 1,840.