At least four Pakistani soldiers and 17 militants were killed Wednesday during clashes in the country's northwest.

Security officials say troops were conducting a search operation in the Jogi village of Kurram tribal agency when they were attacked by a group of militants.

More than 21 people were killed in the ensuing gunbattle. The death toll could not be independently verified since journalists do not have access to the area.

Elsewhere in Pakistan, police say gunmen on motorcycles killed three Shi'ite lawyers in the southern port city of Karachi, in an apparent sectarian attack.

Officials say the dead include a father and a son. One other lawyer was wounded in Wednesday's shooting.

Sunni militants have carried out a number of attacks against Pakistan's minority-Shi'ite Muslim community.

Also Wednesday, local police say at least nine miners are feared dead after they were buried in a landslide in the northwestern province of Khyber-Pakhtunkhwa.

Authorities say heavy rain was hampering rescuers, who were using shovels to try and uncover the trapped miners in the mountainous village of Tharnawai.