Twin bomb attacks have rocked Pakistan's capital Islamabad, killing one person and injuring two others, officials have said.

The first blast took place around 2am on Saturday at Super Market, an upmarket shopping area close to the city centre in an area known as F6.

The second occurred about half an hour later in the parking area of a car dealership in another market in an area known as G-9.

"It is not yet clear whether a suicide bomber was involved or not... both of the injured were watchmen," Chaudhry Hafiz Hussain, a senior police official, told the AFP news agency. 

Al Jazeera's Asad Hashim, reporting from Islamabad, said the blast crater at the Super Market site was about 0.5m across, with debris from the explosion hitting several nearby shops.

"Rescue officials at the site said that one person from the scene had been taken into police custody and that a man had suffered injuries to his legs," Hashim reported.

Damage more extensive

"The G9 market blast damage was much more extensive, with the explosives appearing to have been placed inside a parked vehicle. Police said there were no casualties from that explosion.

"The blast debris also hit several shops in the area and the car in which the explosives were laid was completely destroyed," our reporter said.

The police bomb disposal squad was investigating both incidents.

The attacks were the first to strike the capital since an explosion tore through a fruit and vegetable market in April, killing at least 22 people.

Security in the Pakistani capital has been put on high alert, with the interior minister announcing last week that paramilitary troops would be assisting civilian police with law enforcement.

Saturday's incident came after three days of air strikes by the Pakistani military against Taliban hideouts which killed at least 75 people, according to a security official.

A month-long ceasefire between Pakistan and the Taliban expired last month.

Source: Al Jazeera and agencies