Unidentified assailants fired rockets and detonated bombs in southwestern Pakistan, damaging a high-voltage power line and a railway track, but causing no injuries, officials and police said Thursday. It was not immediately clear who was behind late Wednesday's attacks in Baluchistan province, which came hours after the army announced it was setting up a base in Sui, a tribal region in the province where hundreds of rockets this month hit the country's gas fields. The Jan. 7-11 rocket attacks killed at least eight soldiers and civilians and forced a temporary shutdown at a gas plant and pipeline, disrupting supplies of natural gas across the country.