Bhopal, Sep 17 - At least six people, including a man and his two sons, were killed when a three-storied house collapsed in Madhya Pradesh's Katni town early Thursday.

Police said the incident occurred at about 3 a.m. in Ishwarpuri locality in Katni, about 350 km from here.

Construction was underway on a fourth floor despite the building being old.

'Of the 23 people trapped under the debris of the house, six were killed on the spot while 17 were taken out safely,' Katni Superintendent of Police S.P. Singh told IANS over the phone.

Among those killed were the house owner Omprakash Katchhwaha (55), his sons Ajay (35) and Sanjay (30), as well as Lali Katchhwaha (50), Kalpu Dhuria (40) and Ravi (30).

According to Singh, rescue work started immediately with civic and district administration officials reaching the spot. Of the 17 injured, one is in a critical condition and has been sent to Jabalpur for treatment while the others have been admitted to a hospital in Katni.

The district administration has ordered an inquiry.