The attack took place around 1.30 a.m. Friday in Alipur area of west Delhi.
Police constable Shankar Singh, 32, was stabbed in his neck by Lalit Kumar, a fourth grade employee of North Delhi Power Limited (NDPL).
He was rushed to a hospital where his condition is stated to be out of danger.
lalitb Kumar was arrested and booked for attempt to murder.
A police officer said that Shankar Singh along with sub-inspector Satveer had gone to Alipur to attend a quarrel call.
"On reaching the house of the accused, the constable found that he was beating his wife. When the constable tried to intervene, he was stabbed," said the officer.
"The accused was in an inebriated condition at the time of the incident," he added.
--IANS (Posted on 10-01-2014)