Suspected militants dressed as policemen kidnapped about 60 people in troubled northwestern Pakistan near the Afghan border on Saturday, government and police officials said.
Heavily armed militants first seized a vehicle belonging to the government power utility in the Kurram region and kidnapped four people travelling inside. The vehicle was set on fire.
Shortly afterwards, several vehicles were seized from a convoy of civilians travelling to Parachinar, the main city in Kurram.
Officials initially said 30 people were kidnapped but later said 57 people had been taken from the convoy.
"The militants were posing as policemen and wearing police uniforms," said Mir Chaman, a senior police official in the nearby town of Thal.
Government officials in Kurram confirmed the incident and said efforts were under way to recover the kidnapped people.
The Pakistani military has mounted offensives against militants in their strongholds in the northwest over the past year, largely clearing several areas, killing hundreds of militants and destroying their bases.
A large number of militants, officials say, have fled to Kurram and neighbouring regions after the military launched a major operation against them in their South Waziristan bastion near the Afghan border in mid-October last year.
Security forces have intensified air strikes on militant targets in Kurram and adjoining areas in recent weeks.
The militants have shown resilience and carried out a wave of suicide and bomb attacks, mainly in the northwest, killing hundreds of people.