Lucknow, Apr 27 (IANS): A security guard at a builder's office in Noida, abutting the national capital, Saturday opened fire at agitating labourers, who erupted in anger and pelted stones and set two vehicles on fire, police said. One labourer was injured in the firing.

The incident occurred Saturday morning in Noida's Sector 82. A car and a two-wheeler were set ablaze by the workers, police said.

A group of labourers had an altercation with the management of a construction company over their daily wages. The situation turned ugly when the security guard opened fire on the labourers in an attempt to disperse them.

One bullet grazed a labourer, and angry labourers went on the rampage, police said.

Four other labourers were injured in the melee following the shooting. All five are under treatment in a city hospital.

Senior Superintendent of Police (SSP) Noida Pritinder Singh told IANS that the incident occurred at the office of 3C Construction Company. He said the situation was quickly brought under control.

"We mediated between the two sides and hope some solution will soon be found," the police official said, adding that additional police forces have been deployed at the site.

Policemen are yet to round up the security guard who opened fire.