CHARSADDA - Hujra of Commissioner Kohat and house of his uncle were damaged in separate bomb blast incidents at tehsil Tangi, district Charsadda late on Sunday night, police said. Planted by unknown miscreants, a bomb placed adjacent to the wall of the hujra (guest house) of Commissioner Kohat, Khalid Khan Umerzai, situated at Farichkhel Umerzai village, in tehsil Tangi, went off with a big bang. As a result, wall and a room were partially damaged and luckily three servants present inside the guesthouse at the time of the blast remained unhurt. Police said that the first incident happened at 10:45 pm. After a while, another blast was heard in the same locality. This time, the house of Sarwar Khan Umerzai, uncle of the Commissioner Kohat, Khalid Khan Umerzai, was hit in the bomb blast placed by unidentified miscreants, damaging three rooms partially in the occurrence. Police rushed to sites of the blasts and launched a search operation, and at least four suspected men were arrested, who were later shifted to unknown location for further interrogation. According to officials of the bomb disposal squad, about 1,000 and 500 grams explosives were used in both the blasts respectively. The ear-splitting voice of the explosions forced people to get out of their houses. Windowpanes of adjacent houses and a mosque situated in the locality were also smashed. Police has registered FIRs against unknown elements and started further investigation into the incidents.