Pakistanis have been urging the government to set aside political bickering and tackle extremist violence and economic downturn — challenges underscored Tuesday by a bombing outside a hospital and new battles between the army and militants.

On Tuesday, police said security forces backed by helicopter gunships and artillery pounded insurgents in the border area of Bajur, killing 11 suspected extremists and five civilians. A separate battle in the same region killed 13 militants and five soldiers, officials said.

Meanwhile, a suicide bomb attack killed 26 people and wounded 35 outside a hospital. The Taliban, claimed responsibility for the explosion.

But, as it has for months, the issue of judges revealed itself as a severe strain in the alliance between the two main parties that won February parliamentary elections after running against Musharraf.

The ruling coalition was founded on a pledge to restore the justices quickly. But while former Prime Minister Nawaz Sharif has pushed hard to get them back on the bench, the leader of the coalition’s biggest bloc, Asif Ali Zardari, has stalled their restoration.

After a four-hour meeting with Zardari on Tuesday, Sharif and his senior party lieutenants abruptly walked out, jumping into a convoy of cars without announcing any progress.