LUCKNOW, Sept. 6 -- Four labourers were injured when a residential boundary wall collapsed during excavation under a drain construction project in Rajajipuram D-Block on Friday afternoon. The condition of one of the four labourers trapped under the debris is critical, officials said.

The drain was being constructed by AM Construction, a private firm operating under the Uttar Pradesh State Bridge Corporation. According to sources, the company allegedly has a history of safety violations but it continues to secure government contracts owing to its proximity to influential political and bureaucratic circles.

Eyewitnesses and local residents alleged that excavation began without any safety precautions while approach road work for an overbri...