At least 36 people were killed Tuesday in an attack on a stone quarry in Kenya's Mandera town.According to officials, gunmen opened fire at the quarry after separating Muslims and non-Muslims, Al Jazeera reported.The victims are reportedly miners who were working in the quarry, located just outside the town.Police have launched a probe into the incident.The scene of the latest attack is about 30 km from the Nov 22 raid on a bus in which 28 non-Muslims were separated from the Muslim travellers before being executed.Armed group al-Shabab claimed responsibility for the bus attack.The shooting in the quarry comes after an attack on a night club in the Kenyan town of Wajir Monday night.One person was killed and at least 12 injured as gunmen hurled grenades and sprayed bullets at the building.