DERA ISMAIL KHAN, Pakistan - The Pakistani Taliban has formally ended a 40-day cease-fire but is still open to talks with the government, a spokesman said Wednesday.

Government negotiators were not immediately available to confirm if talks would continue.

Shahidullah Shahid said the insurgents were not extending the cease-fire, which began on March 1, because the government had continued to arrest people and had killed more than 50 people associated with the insurgency.

The government has also continued to carry out raids and had arrested more than 200 people, he said. Shahid also complained that unidentified Taliban prisoners had been tortured in prison.

"However, the talks will continue with sincerity and seriousness and in case there is clear progress from the government side, [the Taliban] will not hesitate to take a serious step," Shahid said in a statement.

Peace talks between the Taliban and the government began in February, but the first round collapsed after less than a week because the Taliban bombed a bus full of police and executed 23 kidnapped men from a government paramilitary force.

The government suspended talks and threatened to launch a military operation against Taliban bases. Talks only resumed after the Taliban declared a cease-fire on March 1.

Since then, the government has released a few dozen low-level noncombatant prisoners, but the Taliban wants hundreds of men released and the army to pull back from tribal areas bordering Afghanistan.