A car bomb exploded Friday next to a police station in northwestern Pakistan, killing three people and ending a five-week lull in the deadly explosions that have plagued the country.

A spokesman for Pakistani Taliban militants claimed responsibility for the blast, but said that the attack was planned before they took part in peace talks launched by the government — and that they remained committed to those negotiations.

The bomb went off between the police station and a market area in the city of Mardan at about 6 a.m. The explosion left huge piles of concrete, brick and metal in the street, while collapsing some roofs and blasting a giant hole in one nearby building's wall.

City police official Javed Khan said one police officer was killed, along with the owner of a small restaurant and one of his staff. Twenty-six people, including 18 policemen, were wounded. Six people were in serious condition at hospitals in Mardan and the regional capital, Peshawar.

Maulvi Umar, a spokesman for an umbrella group called Tehrik-e-Taliban Pakistan, said its militants carried out the attack to avenge the death of a man named Hafiz Saidul Haq. Umar said police shot and killed Haq about 10 days ago when he came to Mardan for his brother's wedding.

The umbrella group distributed a flier earlier this week urging its followers to observe a cease-fire to give peace talks a chance. Umar said the decision to avenge Haq's death had been made earlier.

"We have a cease-fire with the government. But wherever the government will take action against us and will kill our friends, we will take revenge," Umar told an Associated Press reporter by telephone from an undisclosed location.

He said the Taliban have given a "good response" to the government's offer of talks, which were being carried out through tribal leaders. "We have not reached a final stage yet. We have given a positive response. The negotiations are ongoing," he said.

Pakistani Prime Minister Yousaf Raza Gilani condemned the blast, saying "such cowardice acts of violence would not deter our determination to fight the menace of terrorism."

Gilani's coalition government has sought to distance itself from the strong-arm tactics of the previous government led by the allies of President Pervez Musharraf. But while the new government has pushed for dialogue with militants, it also has insisted it will only talk to those groups who renounce violence.

Mohammad Adeel, a leader of one of the parties in the new government, said the latest blast would not derail the talks.

"Even in the peace talks these things happen. Even after the agreement some people will come and they will break the agreement but we will be very patient," Adeel said.

He said he could not predict "how many days, how many weeks or how many months" it would take to reach an agreement.

Pakistan had enjoyed a lull in violence since the new government took office. The last deadly bombing was a suicide blast that killed five soldiers in the South Waziristan region on March 20.

Zahid Khan, like Adeel a leader of the Awami National Party, said Thursday that government envoys were in peace talks with elders of the Mahsud tribe in South Waziristan, a militant stronghold. The tribe includes Baitullah Mehsud, the leader of Tehrik-e-Taliban Pakistan.

The fliers distributed in its name warned that those who disobeyed the order to observe the cease-fire would be "strung upside down in public and punished."

Umar has said militants across the region were ready for peace if the government met their demands to withdraw the army and release militant prisoners. But he has also insisted they will continue to attack U.S. forces in neighboring Afghanistan.

Mehsud is wanted for a series of suicide attacks in Pakistan, and the previous government accused him of Bhutto's assassination in December. He reportedly denied involvement. The new government is led by Bhutto's party, which has not singled out Mehsud in her killing.

U.S. officials have voiced some support for the government's peace initiative, while urging it to exclude Taliban and Al Qaeda figures suspected of orchestrating attacks in Afghanistan and Pakistan — and perhaps plotting major terrorist attacks in the West. The U.S. has expressed concern that militants have taken advantage of past peace deals to regroup.