At least seven people have been killed in twin bombings in the north-western Pakistani city of Peshawar, police say.

巴基斯坦警方称，西北部城市华沙发生两起爆炸事故，至少7人死亡。

In the first incident, four police officers and a child were killed when a remote-controlled bomb exploded near a police vehicle in the Lahori Gate area.

Later, a woman suicide bomber² killed herself and another woman, possibly her companion, by detonating（引爆） her jacket.

She was trying to target the police checkpoint about 400m from the spot where the police vehicle was hit.

Militant³ attacks in Pakistan have risen sharply since May, when US commandos（突击队） killed al-Qaeda leader Osama Bin¹ Laden⁴.

Since then, a paramilitary（准军事的） academy, a naval⁵ base, government buildings, a police station and a US consulate⁶（领事） convoy⁷ have been attacked.

In the first attack on Thursday morning, the explosive device was hidden in a handcart（手推车） parked at the roadside and detonated remotely when police approached, police officer Ijaz Khan told reporters.

Their vehicle was transporting over two dozen policemen from Kotwali police station in the eastern part of the city to the Police Lines near the city centre, he said.

The vehicle was wrecked⁸ in the blast and a group of schoolboys were at the site when the bomb exploded.

A 12-year-old boy was among those killed. At least 21 people, including 17 policemen, were injured in the blast.

In the second attack, police said the bomber appeared to be a woman about 16 or 17 years old. Her clothes suggested she could have been from the tribal⁹ region.

The other woman appeared to be over 50, they said.

The woman's explosives-laden jacket failed to detonate properly, reports said.

The BBC's M Ilyas Khan in Islamabad says the attacks are the first in Peshawar in recent weeks, and come a day after a deadly drone strike that killed at least 18 fighters of the Haqqani network in North Waziristan.