At least four people were killed and 32 others injured when a hand grenade was hurled at a wedding ceremony in Dandai Saidgai village in North Waziristan, a senior political administration official told The Express Tribune.The marriage ceremony came under attack when unidentified militants threw a hand grenade into the house of Shandi Gul in Dandai. At least five critically injured victims have been moved to Peshawar for medical assistance while others were moved to the Agency Hospital in Miranshah. The official said that the injured included at least seven children and many wounded were critical.Earlier this month, a security official was martyred and three others injured when a bomb disposal unit of Pakistan Army was targeted by an Improvised Explosive Device (IED) in North Waziristan.The incident took place in the Dre Wastay area of Tehsil Datta Khel. Official sources said that the area was sealed off and movement was restricted.