ISLAMABAD - Gunmen riding a motorbike Tuesday sprayed bullets into the car of an army brigadier in Pakistan's capital Islamabad for a second time in less than a week, police said.

No one was hurt in the morning attack in the busy I-9 residential neighbourhood and the gunmen fled, police officer Khurshid Khan told AFP.

"Two gunmen on a motorcycle sprayed bullets on the car of Brigadier Waqar Ahmed but he, his mother and his driver were unhurt," said Khan.

Tensions are high in Islamabad following a spike in attacks blamed on Taliban and Al-Qaeda-linked extremists which has left nearly 200 people dead this month in the frontline state in the US-led "war on terror".

On Thursday, gunmen attacked an army jeep in Islamabad, killing a brigadier on leave from a UN peacekeeping mission in Sudan and his driver.

The military has been embarrassed by a series of recent attacks, including an audacious assault this month on the army headquarters in Rawalpindi claimed by the Tehreek-e-Taliban in Pakistan (TTP) movement.

Pakistan has vowed to crush the network, pressing an 11-day ground and air offensive targeting TTP in their South Waziristan stronghold along the Afghan border where Al-Qaeda is accused of plotting attacks on the West.