NEW DELHI: The Pakistani government's continual enforcement of blasphemy laws is one among many reasons cited by the US today in warning its citizens against traveling to Pakistan "Sectarian violence remains a serious threat throughout Pakistan, and the Government of Pakistan continues to enforce blasphemy laws. Religious minority communities have been victims of targeted killings and accusations of blasphemy," said the advisory published on the state department website.In fact, US aviation authorities too have issued an advisory to its airmen."The Federal Aviation Administration has issued a NOTAM (Notice to Airmen) concerning the risks to civil aviation operating in Pakistan, particularly at low altitude, during the arrival and departure phases of flight, and when on the ground, due to extremist/militant activity," The advisory said.Further, because of "significant terrorist violence, including sectarian attacks" the US state department warned that unless it's "essential" it's best US citizens avoid going to Pakistan.Terrorists have actively targeted Americans, the US said."Evidence suggests that some victims of terrorist activity have been targeted because they are Americans," said the advisory published on the state department website.The advisory said there's evidence about targeted terrorist attacks also on NGO employees and humanitarian and aid workers."Targeted attacks against government officials, humanitarian and non-governmental organization (NGO) employees, tribal elders, and law enforcement personnel are common. Throughout Pakistan, foreign and indigenous terrorist groups continue to pose a danger to U.S. citizens," the advisory added.