Militants have attacked a prison in northwestern Pakistan in an apparent attempt to free jailed Taliban and al-Qaida terrorists. Witnesses say security forces are engaged in a firefight with the attackers of the prison in the town of Dera Ismail Khan, as many as 250 convicted terrorists are believed to be held in that prison. _________________________武装分子袭击了巴基斯坦西北部一座监狱,意图显然是要释放囚禁在内的塔利班和基地组织恐怖分子.目击者称安全部队与袭击监狱的武装分子在德拉伊斯梅尔汗县交火,该监狱内有多达250名已被定罪的恐怖分子. ______________________