Karimnagar (Telangana), Dec 22 (PTI): In a frenzied sword attack, a 28-year-old software engineer today left 22 people including his parents and three constables injured before being fatally shot by police.

The attacker's parents and an auto driver are in a critical condition. The policemen, who suffered serious injuries as they tried to stop him, and the other wounded were also undergoing treatment at a local hospital.

According to Karimnagar Deputy Superintendent of Police J Rama Rao, the trouble began at 7 AM after Balvinder Singh alias Babloo (28), of Laxmi Nagar locality in Karimnagar town, entered into an altercation with his parents --Amruth Singh and Baby Kaur--and allegedly attacked them with a sword.

Leaving his parents lying unconscious in a pool of blood, Balvinder ran out of his house wielding the sword and began randomly attacking passers-by and people on the road, police alleged.

It was a scary scene as an auto-driver and a dozen other victims were bleeding profusely, eyewitnesses said.

As the police patrol team reached the spot, Balvinder attacked three constables and wounded them seriously.

Subsequently, police opened fire.

Balvinder was then taken into custody and shifted to Government District Head Quarters hospital here, where he died within three hours of being admitted, hospital sources said.

Balvinder was working in a company in Bangalore.

His parents and the injured auto driver Narayana, also admitted in the same hospital, are said to be in a critical condition.

Further investigations are underway, the DSP said.