As many as six militants have been killed while four security personnel injured when the former assailed Spaina Police Station at Darra Adam Khel.Sources said the miscreants fired five rockets at the said police station injuring four security personnel.The attack was retaliated by the police, claiming six militants and injuring many others.The security forces cordoned off the area and launched search operation. Meanwhile, a man was killed due to firing by the security forces.DCO Kohat told Dunya News that the militants also opened fire at a passenger coach in which two got injured.