Government on Wednesday probed suspected links between pro-Taliban militants and the twin suicide blasts that killed 31 people and heightened the crisis facing President Pervez Musharraf.
The bombings on Tuesday in Rawalpindi where the army is based, added to insecurity in the country as military ruler Musharraf seeks re-election as president in the face of mounting opposition. One bomber blew himself up on a bus carrying defence ministry workers and another struck on a route used by army officers to travel to the military headquarters in the sprawling but heavily-secured city.
Interior ministry spokesman Brigadier Javed Cheema said there were suspected links to pro-Taliban militants backed by al Qaeda who are fighting military operations in Pakistan's lawless tribal areas bordering Afghanistan.
Investigators are focusing on Baitullah Mehsud, one of the most senior militant commanders in the region, who is based in the semi-autonomous district of South Waziristan, he said, an area largely contemptuous of Musharraf's rule. "No one has claimed responsibility but the previous several attacks were linked to Baitullah Mehsud," Cheema told AFP. "The investigations are continuing."
Officials have previously connected Mehsud with the radical clerics who ran the Red Mosque in Islamabad, which government forces besieged and stormed in July in an operation that cost more than 100 lives. Mehsud has reportedly claimed responsibility for a series of attacks on military and government targets since then, including what he claims is the abduction of around 150 soldiers in South Waziristan last week. The army insists the soldiers are stranded in the area due to a tribal dispute.
Security sources have said the two attackers who struck on Tuesday may have been the remaining members of team of seven bombers, some allegedly sent by Mehsud, who infiltrated Islamabad and Rawalpindi for Pakistan's independence day celebrations in August.
Five of them have been arrested in recent weeks "but there is a fear that the two others may have carried out the latest attacks," a security official said on condition of anonymity. Security officials said the death toll had risen to 31 after six people wounded in the blasts died in hospital overnight, a senior security official told AFP on condition of anonymity.
Pakistan has been wracked by Islamist violence since the Red Mosque siege, posing further problems for the embattled Musharraf as Washington leans on him to do more to combat the Taliban and Osama bin Laden's al Qaeda network.
US officials have warned of possible unilateral strikes on Pakistan's tribal zone, saying that al Qaeda is using it to plot international attacks and the Taliban hiding there before launching attacks in Afghanistan. Mehsud is one of several key Taliban commanders based in the region. He has been bitterly fighting Pakistani military operations against militants who fled there from Afghanistan after the post-9/11 fall of the Taliban.
The turmoil has left Musharraf increasingly isolated at home, as he pushes for a power-sharing deal with ex-premier Benazir Bhutto to end a political crisis sparked by his suspension of Pakistan's chief justice earlier this year.
Talks between the two sides in Dubai on Tuesday made progress, with hopes that they can overcome differences over Bhutto's demands including that Musharraf should quit the army and give up some powers, officials said.
Musharraf wants to stand for another five-year term as president-in-uniform this month or next, ahead of general elections expected by early this year, but he faces likely legal and political challenges. Another former prime minister and the man Musharraf toppled in 1999, Nawaz Sharif, has also vowed to return home on September 10 to oppose the country's military ruler.