12 other labourers were evacuated from the rubble, according to PTI.
A sub-contractor from Sector 20, Gul Mohammad, who supplied the labourers to the contractor, has been arrested, the police said, reported news agency ANI. It further added that a First Information Report (FIR) has been registered.
Moreover, Ritu Maheshwari, the chief executive officer of Noida Authority, has confirmed that a compensation of Rs 5 lakh – to each of the deceased's kin – will be provided by the contractor.
Police Commissioner and Noida District Magistrate (DM), Suhas LY, are at the location on the instructions of Uttar Pradesh Chief Minister Yogi Adityanath.
Adityanath expressed grief over the incident and directed the district administration to provide treatment to the injured, and instructed the district magistrate and senior police officers to carry out relief work immediately.
Four labourers died in the District Hospital and Kailash Hospital, while 12 have been safely rescued.
The names of the four deceased are Pushpendra (28), Pannalal (18), Amit (18), and Dharamveer.
The Noida DM further added that the Noida Authority had given a contract for drainage repair work near Jal Vayu Vihar in Sector 21 and as the drain was being cleaned, the 100 metre wall collapsed while the labourers were pulling out bricks.
(With inputs from PTI and ANI.)