The rescue operations are on war footing by the local administration with the help of teams of Army and NDRF, to extricate the trapped people.
"11 people have died in the incident, while eight have been rescued. Still, around 35-40 people are believed to be trapped under the debris," district officials said.
Superintendent of state government-run Sir Sayajirao General (SSG) Hospital Dr Deveshwar Pandey told PTI that three women, a six-month old male infant and a 13-year-old boy were among those killed.
VMC commissioner Manish Bhardwaj, city police commissioner Satish Sharma and Mayor Bharat Shah and other senior officials were overseeing the rescue work.
The locals alleged that the buildings collapsed owing to sub-standard material used in the construction.
Atladara is a newly developed locality after merger of Atladara village with Vadodara city. The buildings were constructed by the Vadadora Urban Development Authority (VUDA) in 2002, officials said.
Meanwhile, the Narendra Modi government ordered a high level inquiry into the twin-building collapse.
Modi also announced Rs 2 lakh compensation to the kin of those who have died in the mishap.
