Lucknow, Nov 8 (IANS): Three students have been arrested for allegedly murdering the retired principal of a government polytechnic institute and his wife with sharp edged weapons in Uttar Pradesh's Kanpur district, police said Tuesday.

Varun Kumar, Ajai Singh and Aalam, all about 20 years old, were arrested Monday. The three are accused of killing retired principal J.P. Mishra (65) and his wife Lakshmi (63) on Oct 30 at their residence in Qidwai Nagar, about 80 km from here. They also fled with the valuables in the house.

While Varun Kumar is a third year student of automobile engineering at the Rajkiya Polytechnic in Kanpur, Ajai Singh and Aalam are in the third year of the Bachelor of Computer Application (BCA) course in different private engineering colleges.

All the three used to take tuition from Mishra at his residence.

"We became suspicious only after a neighbour of Mishra told us that he had spotted the three moving suspiciously near the couple's house a day before they were murdered, and that the students ran away after noticing him," police spokesperson Anurag Tiwari told reporters.

"When we interrogated the students, they admitted to have killed the couple with sharp-edged razors and a kitchen knife. Cash, mobile phones and other valuable items looted have been recovered from the three students," he added.