(Updates toll, adds Pakistan's statement)
By Abdul Qadir Sediqi and Rupam Jain
KABUL, May 5 (Reuters) - Afghan forces battled for hours against Taliban insurgents who stormed a police headquarters in the northern city of Pul-e-Khumri, after a suicide bomber blew up his explosive-laden car, killing at least 13 people, officials said on Sunday.
A Taliban militant detonated his Humvee vehicle at the entrance of the police office before a group of eight attackers armed with machine guns rushed in the building, two Afghan officials said.
"Thirteen policemen were killed and 35 others injured," said Nasrat Rahimi, a spokesman at the Interior Ministry in Kabul, adding that 20 civilians were also wounded.
"The complex attack on Baghlan police headquarters has ended with the death of all nine attackers, including the suicide bomber," he said.
The Taliban, which is seeking to restore strict Islamic rule and expel foreign forces from Afghanistan, claimed responsibility for the attack in a busy area of the city with many other residential and commercial buildings.
Taliban fighters frequently capture U.S.-made armored Humvee vehicles from Afghan forces to load with explosives and use as car bombs to breach military fortifications.
Abdul Aleem Ghafari, deputy provincial health director in Pul-e-Khumri, said women and children were among those killed by the blast.
Sunday's raid was the latest in a series of high-profile attacks that have killed and wounded hundreds of civilians in Afghanistan this year and put heavy pressure on the Western-backed government of President Ashraf Ghani.
The Taliban have stepped up attacks on security installations, even as they hold sixth rounds of direct talks with U.S. officials to end the war in Afghanistan.
This week, the group rejected appeals made last week by Afghan President Ashraf Ghani and the U.S. special envoy for peace in Afghanistan, Zalmay Khalilzad, to declare a ceasefire in the 17-year conflict.
Afghan-born U.S. diplomat Khalilzad is leading the talks with the Taliban in Doha to pursue a deal that would bring the withdrawal of foreign forces in return for Taliban security guarantees.
"All sides agreeing to reduce violence is a necessary step toward achieving that outcome and the morally responsible choice to make. We stand ready," Khalilzad wrote on Twitter on Saturday.
Khalilzad's comments came a day after Ghani said he was prepared to call an "immediate" and "permanent" ceasefire.
The Taliban said they will not lay down their arms ahead of the holy month of Ramadan and rejected to hold talks with the Afghan government which they consider an illegitimate “puppet” regime.
Direct talks between the Afghan government and the Taliban collapsed in 2015.
"A ceasefire will only get discussed once a deal about foreign force withdrawal gets finalized," Suhail Shaheen, the Taliban's Doha-based political spokesman, told Reuters.
About 45,000 Afghan security forces have been killed since Ghani took office in September 2014.
The hardline Islamists group now holds sway over more territory than at any point since its ousting by U.S.-led troops after the Sept. 11 attacks on the United States in 2001.
The Resolute Support Mission in Afghanistan consists of 17,000 troops, about half of them from the United States. A smaller number of U.S. troops operate in Afghanistan under a counter-terrorism mission. The United Nations’ top official in Afghanistan, Tadamichi Yamamoto, on Sunday, called on all parties to halt the fighting before Ramadan.
On Sunday, Ghani spoke with Pakistan's Prime Minister Imran Khan to secure fresh backing to hold direct talks with the Taliban, hours after Afghanistan's foreign ministry summoned a senior Pakistani diplomat over cross-border clashes between Pakistani and Afghan troops.
Relations between neighbors, Afghanistan and Pakistan have been plagued by mistrust and at times hostility since Pakistan’s independence in 1947.
For years, Afghanistan and the United States have accused Pakistan of supporting the Taliban as a way for Pakistan to limit the influence of its old rival, India, in Afghanistan.
Pakistan denies that.
Pakistan's role in the ongoing peace negotiations is a delicate one, with Islamabad seeking to avoid showcasing any kind of broad influence over the Taliban.
Khan's office in a statement said the two leaders exchanged views on matters relating to peace, security, and prosperity in Afghanistan and the region.
"The Prime Minister (Imran Khan) underlined that Pakistan will spare no effort to advance the common objectives of building peace in Afghanistan and having a fruitful bilateral relationship between the two brotherly countries," it stated.
Ghani is expected to travel to Pakistan, but travel dates were not made public.
(Additional reporting by James Mackenzie in Islamabad, Writing by Rupam Jain, Editing by Richard Borsuk, Raissa Kasolowsky and David Goodman)