ISLAMABAD -- Pakistani investigators scouring the scene of a weekend suicide bomb attack on police found a severed head as the leader of the ruling party said his government would do everything to stop the bombers.
The toll from the July 6 attack on police, who had been guarding Islamists marking the anniversary of an army commando raid on Islamabad's Red Mosque, rose to 16 as one of the nearly 50 wounded died, police said.
The attack has raised questions about the new government's policy of trying to end militant violence through negotiations and will increase concern about prospects for the country, a nuclear-armed U.S. ally making a transition to civilian rule.
The government is led by the Pakistan People's Party (PPP) of former Prime Minister Benazir Bhutto, who was killed in a suicide attack in Rawalpindi on Dec. 27.
Bhutto's widower, Asif Ali Zardari, who took over as leader of the party after his wife's murder, said in a statement that those behind the "despicable" attack on July 6 were trying to create chaos.
"Pakistan People's Party realizes the grave threat that such terrorist activities pose to the country and the PPP government will do everything possible to check the activities of such elements and those responsible will be brought to justice," he said.
President Pervez Musharraf, whose power has withered since his allies were defeated in a February election and who has been facing calls to step down, warned on July 4 that more radical mosques would emerge if extremism and militancy were not tackled.
The former army chief who took power in a 1999 coup ruled out resigning, saying he was needed to help politicians avoid an economic meltdown and tackle the militant threat.
Investigators at the site discovered a severed head in bushes beside the road where the attack took place, a Reuters photographer said, but police declined to comment on the grisly find.
The heads of suicide bombers are often severed by the explosives strapped to their torsos and can provide vital clues.
Police investigator Falak Sher said an estimated 5 kilograms of explosives had been used in the attack. No suspects had been detained, he said.
The blast happened several hundred meters from the city-center Red Mosque, shortly after a tightly guarded meeting of Islamists there had ended.
Several thousand Islamists, including members of banned groups, had listened to fiery speeches to mark the first anniversary of the army raid on the complex.
More than 100 people were killed when commandos stormed the Red Mosque complex, which included a madrasa or Islamic seminary, on July 10 last year, after a weeklong siege that began when gunmen from the mosque clashed with police outside.
A couple of weeks after the siege, 13 people, most of them policemen, were killed in a suicide bomb attack on police at the opposite end of the same road as the July 6 attack.